nerve activates contraction - mrs. alvarez - quaboag...
TRANSCRIPT
Lecture Presentation by
Patty Bostwick-Taylor
Florence-Darlington Technical College
Chapter 3
Part 1 Cells
Modified by Janice Alvarez
Cells
Cells are the structural units of all living things
The human body has 50 to 100 trillion cells
Four Concepts of the Cell Theory
1 basic structural and functional unit
2 activity of an organism depends on the
collective activities of its cells
3 principle of complementarity
the biochemical activities of cells are
dictated by the relative number of their
specific subcellular structures
ex Muscle cells have a lot of mitochondria
Skin cells do not
4 continuity of life has a cellular basis
Chemical Components of Cells
Most cells are composed of four elements
1 Carbon
2 Hydrogen
3 Oxygen
4 Nitrogen
Cells are about 60 water
Anatomy of a Generalized Cell
In general a cell has three main regions or parts
Nucleus
Cytoplasm
Plasma
membrane
The Nucleus
Contains genetic material deoxyribonucleic acid (DNA)
DNA is needed for building proteins
DNA is necessary for cell reproduction
Nucleus
Rough ER
Nuclear envelope
Chromatin
Nucleolus
Nuclear
pores
The Nuclear Envelope (nuclear membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of
material with the rest of the cell
Encloses the jellylike fluid called the nucleoplasm
Nuclear envelope
Nuclear
pores
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cells
Cells are the structural units of all living things
The human body has 50 to 100 trillion cells
Four Concepts of the Cell Theory
1 basic structural and functional unit
2 activity of an organism depends on the
collective activities of its cells
3 principle of complementarity
the biochemical activities of cells are
dictated by the relative number of their
specific subcellular structures
ex Muscle cells have a lot of mitochondria
Skin cells do not
4 continuity of life has a cellular basis
Chemical Components of Cells
Most cells are composed of four elements
1 Carbon
2 Hydrogen
3 Oxygen
4 Nitrogen
Cells are about 60 water
Anatomy of a Generalized Cell
In general a cell has three main regions or parts
Nucleus
Cytoplasm
Plasma
membrane
The Nucleus
Contains genetic material deoxyribonucleic acid (DNA)
DNA is needed for building proteins
DNA is necessary for cell reproduction
Nucleus
Rough ER
Nuclear envelope
Chromatin
Nucleolus
Nuclear
pores
The Nuclear Envelope (nuclear membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of
material with the rest of the cell
Encloses the jellylike fluid called the nucleoplasm
Nuclear envelope
Nuclear
pores
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Four Concepts of the Cell Theory
1 basic structural and functional unit
2 activity of an organism depends on the
collective activities of its cells
3 principle of complementarity
the biochemical activities of cells are
dictated by the relative number of their
specific subcellular structures
ex Muscle cells have a lot of mitochondria
Skin cells do not
4 continuity of life has a cellular basis
Chemical Components of Cells
Most cells are composed of four elements
1 Carbon
2 Hydrogen
3 Oxygen
4 Nitrogen
Cells are about 60 water
Anatomy of a Generalized Cell
In general a cell has three main regions or parts
Nucleus
Cytoplasm
Plasma
membrane
The Nucleus
Contains genetic material deoxyribonucleic acid (DNA)
DNA is needed for building proteins
DNA is necessary for cell reproduction
Nucleus
Rough ER
Nuclear envelope
Chromatin
Nucleolus
Nuclear
pores
The Nuclear Envelope (nuclear membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of
material with the rest of the cell
Encloses the jellylike fluid called the nucleoplasm
Nuclear envelope
Nuclear
pores
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Chemical Components of Cells
Most cells are composed of four elements
1 Carbon
2 Hydrogen
3 Oxygen
4 Nitrogen
Cells are about 60 water
Anatomy of a Generalized Cell
In general a cell has three main regions or parts
Nucleus
Cytoplasm
Plasma
membrane
The Nucleus
Contains genetic material deoxyribonucleic acid (DNA)
DNA is needed for building proteins
DNA is necessary for cell reproduction
Nucleus
Rough ER
Nuclear envelope
Chromatin
Nucleolus
Nuclear
pores
The Nuclear Envelope (nuclear membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of
material with the rest of the cell
Encloses the jellylike fluid called the nucleoplasm
Nuclear envelope
Nuclear
pores
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Anatomy of a Generalized Cell
In general a cell has three main regions or parts
Nucleus
Cytoplasm
Plasma
membrane
The Nucleus
Contains genetic material deoxyribonucleic acid (DNA)
DNA is needed for building proteins
DNA is necessary for cell reproduction
Nucleus
Rough ER
Nuclear envelope
Chromatin
Nucleolus
Nuclear
pores
The Nuclear Envelope (nuclear membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of
material with the rest of the cell
Encloses the jellylike fluid called the nucleoplasm
Nuclear envelope
Nuclear
pores
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
The Nucleus
Contains genetic material deoxyribonucleic acid (DNA)
DNA is needed for building proteins
DNA is necessary for cell reproduction
Nucleus
Rough ER
Nuclear envelope
Chromatin
Nucleolus
Nuclear
pores
The Nuclear Envelope (nuclear membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of
material with the rest of the cell
Encloses the jellylike fluid called the nucleoplasm
Nuclear envelope
Nuclear
pores
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
The Nuclear Envelope (nuclear membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of
material with the rest of the cell
Encloses the jellylike fluid called the nucleoplasm
Nuclear envelope
Nuclear
pores
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
The Nucleoli
Nucleus contains one or more nucleoli
Sites of ribosome assembly
Ribosomes migrate into the cytoplasm through
nuclear pores to serve as the site of protein synthesis
Nucleolus
Nuclear
pores
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Chromatin
Composed of DNA and protein
Present when the cell is not dividing
Scattered throughout the nucleus
Condenses to form dense rod-like bodies called
chromosomes when the cell divides
Chromatin
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Plasma Membrane
Transparent barrier for cell contents
Contains cell contents
Separates cell contents from surrounding environment
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Plasma Membrane
Fluid mosaic model is constructed of
Phospholipids Cholesterol
Proteins Sugars
Lipid Properties
Hydrophilic
Hydrophobic
Cholesterol role
Protein Role
Sugar group
Glycoprotein glycolipid
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Concept Link
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Plasma Membrane Junctions
Microvilli
Connexon
Underlyingbasementmembrane
Extracellularspace betweencells
Gap
(communicating) junction
Plasmamembranes ofadjacent cells
Desmosome
(anchoring
junction)
Tight
(impermeable)junction
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Chromatin
NucleolusNuclear envelope
Nucleus
Plasma
membrane
Roughendoplasmicreticulum
Ribosomes
Golgi
apparatus
Secretion beingreleased from cellby exocytosisPeroxisome
Intermediate
filaments
Microtubule
Centrioles
Mitochondrion
Lysosome
Cytosol
Smooth
endoplasmic
reticulum
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cytoplasmic Organelles
Specialized cellular compartments
Many are membrane-bound
Compartmentalization is critical for organellersquos ability
to perform specialized functions
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Mitochondria
ldquoPowerhousesrdquo of the cell
Change shape continuously
Mitochondrial wall = double membrane
cristae on the inner membrane
Carry out reactions using oxygen to break down food
Produces ATP for cellular energy
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Ribosomes
Made of protein and ribosomal RNA
Sites of protein synthesis
Found at two locations
Free in the cytoplasm
Attached to the rrough endoplasmic reticulum
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Endoplasmic reticulum (ER)
Rough endoplasmic reticulum
Studded with ribosomes
Synthesizes proteins
Transport vesicles move
proteins within cell
Abundant in cells that make
and export proteins
Smooth endoplasmic reticulum
Functions in lipid metabolism
Detoxification of drugs and
pesticides
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Ribosome
1
1
mRNA
Rough ER
Protein
As the protein is synthesized
on the ribosome it migrates
into the rough ER cistern
Slide 2
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson Education Inc
Ribosome
2
2
mRNA
Rough ER
Protein
In the cistern the protein
folds into its functional shape
Short sugar chains may be
attached to the protein (forming
a glycoprotein)
Slide 3
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson Education Inc
The protein is packaged in a
tiny membranous sac called a
transport vesicle
Ribosome
3
3
mRNA
Rough ER
Protein
Transport
vesicle buds off
Slide 4
Synthesis and Export of Protein
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson Education Inc
The transport vesicle buds
from the rough ER and travels
to the Golgi apparatus for
further processing
Ribosome
4
4
mRNA
Rough ER
Protein
Protein inside
transport vesicle
Slide 5
Synthesis and Export of Protein
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Golgi Apparatus
Stack of flattened membranes with tiny vesicles nearby
Modifies and packages proteins
3 types of packages
Secretory vesicles (pathway 1)
In-house proteins and lipids (pathway 2)
Lysosomes (pathway 3)
Pathway 1
Pathway 2
Pathway 3
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Golgi Apparatus ndash 3 Pathways
Rough ER Cisterns
Transport
vesicleLysosome fuses
with ingested
substances
Pathway 1
Secretory vesicles
Proteins
Secretion by
exocytosis Extracellular fluid
Pathway 2
Pathway 3
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Lysosomes
Membranous ldquobagsrdquo packaged by the Golgi apparatus
Contain enzymes produced by ribosomes
Enzymes digest worn-out or non-useable cell structures
House phagocytes that dispose of bacteria and cell debris
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Peroxisomes
Membranous sacs of oxidase enzymes
Detoxify harmful substances (alcohol and formaldehyde)
Break down free radicals (highly reactive chemicals)
convert to hydrogen peroxide and then to water
Replicate by pinching in half or budding from the ER
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cytoskeleton
Network of protein structures throughout the cytoplasm
Provides the cell with an internal framework
Three different types of elements
1 Microtubules
2 Intermediate filaments
3 Microfilaments
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Centrioles
Rod-shaped bodies of microtubules
Make more microtubules
Forms the mitotic spindle during cell division
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cell Extensions ndash found in some cells
Flagella propels the cell
only cell with flagella in humans is sperm
Microvilli Increase surface area for absorption
Cilia move materials across
the cell surface
Respiratory system
moves mucus
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cell Diversity
The human body houses over 200 different cell types
Cells vary in length
112000 inch 1 yard (nerve cells)
Cell shape reflects its specialized function
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cells Can Connect Body Parts
Fibroblast
Secretes cable-like fibers
Erythrocyte (red blood cell)
Carries oxygen in the bloodstream
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Cells Can Cover and Line Body Organs
Epithelial cell
Packs together in sheets
Intermediate fibers resist tearing during rubbing or pulling
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cells Can Move Organs and Body Parts
Skeletal muscle and smooth muscle cells
Contractile filaments allow cells to shorten forcefully
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cells Can Store Nutrients
Fat cells
Lipid droplets stored in cytoplasm
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cells Can Fight Disease
Macrophage (a phagocytic cell)
Digests infectious microorganisms
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cells Can Gather Information amp Control the Body
Nerve cell (neuron)
Receives and transmits messages to other body parts
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cells Can Create a New Person
Oocyte (female)
Largest cell in the body
Divides to become an
embryo upon fertilization
Sperm (male)
Built for swimming to the
egg for fertilization
Flagellum acts as a
motile whip
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Each Cell Has the Ability to
Metabolize
Digest food
Dispose of wastes
Reproduce
Grow
Move
Respond to a stimulus
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Day 2
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Transport Across the Plasma Membrane
Plasma membrane is a selectively permeable barrier
Some materials can pass through
Other materials can not pass
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Two Basic Methods to Transport Materials
Passive processes
No energy (ATP) is required
Active processes
Cell must provide metabolic energy (ATP)
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
AampP FlixTM Membrane Transport
copy 2015 Pearson
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Diffusion ndash Passive Transport
Particles tend to distribute themselves evenly
Driving force is the kinetic energy (energy of motion) that causes
the molecules to move about randomly
Molecule movement is from high concentration to low
concentration or down a concentration gradient
Size of molecule and temperature affects the speed of diffusion
The smaller the molecule the faster the rate of diffusion
The warmer the molecule the faster the rate of diffusion
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Diffusion
Molecules will diffuse if they are
small enough to pass through the
membranersquos pores (channels
formed by membrane proteins)
lipid-soluble
assisted by a membrane carrier
Cytoplasm
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Simple Diffusion
Unassisted
Solutes are lipid-soluble
or small to pass through
membrane pores
Cytoplasm
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Osmosis (diffusion of water)
Highly polar water
molecules easily cross
the plasma membrane
through aquaporins
Water moves down its
concentration gradient
Water
molecules
Lipid
bilayer
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Solution Types Isotonic Hypertonic Hypotonic
Isotonic solutions
have the same solute and water
concentrations as cells
no visible changes in the cell
Hypertonic solutions
contain more solutes than the cells do
cells will begin to shrink
Hypotonic solutions
contain fewer solutes (more water) than
the cells do
cells will plump
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Facilitated Diffusion
Transports lipid-insoluble and large substances
Glucose is transported via facilitated diffusion
Protein membrane channels or protein molecules
that act as carriers are usedLipid-
insoluble
solutes
Small lipid-
insoluble
solutes
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Filtration
Water and solutes are forced through a membrane
by fluid or hydrostatic pressure
A pressure gradient must exist
Solute-containing fluid (filtrate) is pushed from a high-
pressure area to a lower-pressure area
Filtration is critical for the kidneys to work properly
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Active Processes
Solute pumping
Requires protein carriers to transport substances that
Are too large to travel through membrane channels
May not be lipid-soluble
Move against a concentration gradient
ATP is used
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Active Transport
Solute pumps to move
amino acids
some sugars
ions
ATP energizes solute pumps
substances are moved against concentration gradient
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Sodium-Potassium Pump (for the salty banana)
Sodium is transported out of the cell
Potassium is transported into the cell
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Sodium-Potassium Pump
httpswwwyoutubecomwatchv=GTHWig1vOnYampfeature=youtube
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Transport Using Vesicles (Vesicular Transport)
Move material without actually crossing the membrane
Exocytosis (exit)
Endocytosis (enter)
Phagocytosis ndash solids (eat)
Pinocytosis ndash liquids (drink)
Electron micrograph of a
secretory vesicle in
exocytosis (190000times)
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Day 3
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cell Life Cycle
Changes in cell from time it is formed until it divides
Two major periods
1 Interphase
Cell grows
Cell carries on metabolic processes
Longer phase of the cell cycle
2 Cell division
Cell replicates itself
Produce cells for growth
and repair processes
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
DNA Replication
Genetic material is duplicated
and readies a cell for division
into two cells
Occurs toward the end of
interphase
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cell Division Mitosis and Cytokinesis
Mitosismdashdivision of the nucleus
two daughter nuclei form
Cytokinesismdashdivision of the cytoplasm
two daughter cells form
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
AampP Flixtrade Mitosis
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Stages of Mitosis
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Mitosis (PMAT)
Its all about the chromosomeshellip
Pair up
Move to Middle
Apart
Two nuclei
And thenhellip CYTOKINESIS
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Stages of Mitosis
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Cytokinesis ndash Division of the cytoplasm
Starts in late anaphase and finishes in telophase
Cleavage furrow pinches the cells into two parts
Contractile ring made of microfilaments
Two daughter cells form
In some cases the cytoplasm is not divided
Binucleate or multinucleate cells result
Common in the liver
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Protein Synthesis
DNA serves as a blueprint for making proteins
Gene DNA segment that carries a blueprint for
building one protein or polypeptide chain
Proteins have many functions
Fibrous (structural) proteins are the building
materials for cells
Globular (functional) proteins act as enzymes
(biological catalysts)
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Protein Synthesis
DNA information is coded into triplets
Triplets
Contain three bases
Call for a particular amino acid
For example a DNA sequence of AAA specifies the
amino acid phenylalanine
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Protein Synthesis
Most ribosomes the manufacturing sites of
proteins are located in the cytoplasm
DNA never leaves the nucleus in interphase cells
DNA requires a decoder and a messenger to build
proteins both are functions carried out by RNA
(ribonucleic acid)
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Protein Synthesis
How does RNA differ from DNA RNA
Is single-stranded
Contains ribose sugar instead of deoxyribose
Contains uracil (U) base instead of thymine (T)
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Role of RNA
Transfer RNA (tRNA)
Transfers appropriate amino acids to the ribosome
for building the protein
Ribosomal RNA (rRNA)
Helps form the ribosomes where proteins are built
Messenger RNA (mRNA)
Carries the instructions for building a protein from the
nucleus to the ribosome
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Role of RNA
Protein synthesis involves two major phases
Transcription
Translation
We will detail these two phases next
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Protein Synthesis
Transcription
Transfer of information from DNArsquos base sequence to
the complementary base sequence of mRNA
Only DNA and mRNA are involved
Triplets are the three-base sequence specifying a
particular amino acid on the DNA gene
Codons are the corresponding three-base
sequences on mRNA
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Protein Synthesis
Example of transcription
DNA triplets AAT-CGT-TCG
mRNA codons UUA-GCA-AGC
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
mRNA specifying one
polypeptide is made on
DNA template
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
mRNA
Figure 316 Protein synthesis
Nuclear membrane
2
1
3
4
5
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct aminoacid attached toeach species oftRNA by anenzyme
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
Met
Gly
Ser
Phe
Ala
Slide 1
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
Slide 2
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
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Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
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REVIEW of Cell Activity
copy 2015 Pearson
Protein Synthesis
Translation
Base sequence of nucleic acid is translated to an
amino acid sequence
Amino acids are the building blocks of proteins
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Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
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Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
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Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316 (step 1 covers
transcription)
2 mRNA leaves nucleus and attaches to ribosome
and translation begins
3 Incoming tRNA recognizes a complementary mRNA
codon calling for its amino acid by binding via its
anticodon to the codon
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
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Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
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Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
mRNA leaves
nucleus and attaches
to ribosome and
translation begins
mRNA specifying one
polypeptide is made on
DNA template
Figure 316 Protein synthesis (1 of 2)
mRNA
Nuclear membrane
1
Nuclear pore
Nucleus
(site of transcription)DNA
Amino
acids
Cytoplasm
(site of translation)
Synthetase
enzyme
Correct amino
acid attached to
each species of
tRNA by an
enzyme
2
Slide 3
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Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
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Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
Figure 316 Protein synthesis (2 of 2)
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
Slide 4
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
Protein Synthesis
Translation (continued)
Steps correspond to Figure 316
4 As the ribosome moves along the mRNA a new
amino acid is added to the growing protein chain
5 Released tRNA reenters the cytoplasmic pool
ready to be recharged with a new amino acid
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson Education Inc
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
Met
Gly
Ser
Phe
Ala
Slide 5
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson Education Inc
Released tRNAreenters thecytoplasmic poolready to be rechargedwith a new aminoacid
Incoming tRNArecognizes acomplementarymRNA codon callingfor its amino acid bybinding via its anticodonto the codon
As the ribosomemoves along the mRNAa new amino acid isadded to the growingprotein chain
Figure 316 Protein synthesis (2 of 2)
Growing
polypeptide
chain
Peptide bond
tRNA ldquoheadrdquo
bearing anticodon
Large ribosomal subunit
Codon
Portion of
mRNA already
translated
Small ribosomal subunit
Direction ofribosome advanceribosome moves themRNA strand alongsequentially as each
codon is read
3
4
5
Met
Gly
Ser
Phe
Ala
Slide 6
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
Concept Link
copy 2015 Pearson
copy 2015 Pearson
REVIEW of Cell Activity
copy 2015 Pearson
REVIEW of Cell Activity
REVIEW of Cell Activity
