UNIT 4 CELL BOUNDARIES AND TRANSPORT

Unit 4 test: October 16, 2018

CELL BOUNDARIES

Cell Wall–_____________ & _____________ the cell

– Lies outside of the __________________

– Is made of ______________& ______________

–Plant cell walls are mainly ___________

– Fungi cell walls are mainly ___________

support protect

cell membranecarbohydrates

proteins

cellulose

chitin

• II. CELL Membrane

• A cell is defined as the smallest _________ unit of life. In order to maintain ___________, _______ must be moved into the cell and ______ must be transported out of the cell. In addition, some cells produce _________ and other materials designated for export. All materials moving in and out of the cell must pass through the____________a ______________boundary found in ____ cells.

CELL BOUNDARIES

workinghomeostasis nutrients

wastes

hormones

cell membrane semi permeableall

Cell Membrane in a Nutshell (187-190)

– Made mainly of ____________ & _________

– Hydrophobic tails of phospholipids make molecules line up as a

_______ with polar head facing

_____ and nonpolar

tails facing ___.

phospholipid proteins

bilayerout

in

Function

– Membranes are __________________ = Semi-permeable, picky

– Allow certain molecules to pass through; but keeps others out

– __________ what enters & leaves the cell

– Helps maintain ___________

selectively permeable

Controls

homeostasis

Other components of the cell membrane

– Proteins-• Peripheral- on the inside or outside surface. Can be

partially embedded into the cell membrane or can be found attached to an integral membrane protein.–On the outside surface, ____________ to inside

cell; “receptor protein”–On the inside surface, __________ the call

membrane to the cell’s internal support structure (cytoskeleton) giving cell its shape. “Anchor proteins”

• Transport proteins (also called integral)-_______________________ through the membrane; used as channels or tunnels to move things in or out of the cell

transmit signals

anchors

embedded all the way

Other components of the cell membrane

•Cholesterol- only in _______ cells

–Helps prevent fatty acid tails from ________ together

–Provides ________ for ________

cell (no cell wall)

animal

sticking

stability animal

Other components of the cell membrane

• Carbohydrates- in chain form; on outside surface

–Used to ____________ ; cell ID tags

–If found on top of a protein the whole structure is called a _____________

–If found on top of a phospholipid the whole structure is called a _________

recognize self

glycoprotein

glycolipid

Label the following cell membrane

1. Transport/Integral Protein2. Peripheral Protein on the inside 3. Glycoprotein4. Glycolipid5. Cholesterol

CARBOHYDRATES

• On the outside of the cell membrane to identify as “self or non-self”

PROTEINS

• Embedded in the bilayer

• Serve as channels & pumps for transport of specific molecules across the cell membrane

What biomolecule regulates what can enter or leave the cell w/o a channel or

pump?

A. Lipid

B. Carbohydrate

C. Protein

D. Nucleic Acid

What biomolecule Serve as channels & pumps for transport

A. Lipid

B. Carbohydrate

C. Protein

D. Nucleic Acid

What biomolecule is used to toidentify as “self or non-self”

A. Lipid

B. Carbohydrate

C. Protein

D. Nucleic Acid

Non-polar, middle portion of cell membrane

A. a

B. b

C. c

D. d

E. e

Embedded in cell membrane, serve as channels & pumps

A. a

B. b

C. c

D. d

E. e

Polar portion of cell membrane oriented towards water

A. a

B. b

C. c

D. d

E. e

Provides stability for animal cell membrane

A. a

B. b

C. c

D. d

E. e

Serve as “id” tags for cell

A. a

B. b

C. c

D. d

E. e

CELL TRANSPORT

Passive Transport• Does NOT require ________

• Movement of substances from a ______concentration to ______

• 3 Types:o Diffusion

o Facilitated diffusion

o Osmosis

energy

highlow

DIFFUSION

Diffusion:

• Random movement of molecules in a ________or _____

Many substances move across

the ________________ by

diffusion, for example

_________________________

• Example: odor gradually

fills a room

cell membrane

water, oxygen, & small molecules

liquidgas

FACILITATED DIFFUSION

Facilitated Diffusion:

• Diffusion of _____________through a _____________

• Ex: glucose as it is transported across a cell membrane by a protein channel

large molecules

protein channel

FACILITATED DIFFUSION

• Protein channels provide larger openings for larger molecules like ________________. In addition, due to the _________ fatty acid tails that make up most of the phospholipid bilayer, _____ molecules and _____ utilize protein channels.

glucose, & fructose

non-polar

polar ions

FACILITATED DIFFUSION

• This includes ________, which utilizes specialized protein channels known as ________________.

***A protein pump is active transport so this sentence should be in the active transport section

Na & K

Protein pumps

OSMOSIS

Osmosis:

• Diffusion of ________from a _______ water concentration to a ________ water concentration through a __________________ membrane. There are comparative terms used to describe the water versus solute concentration on either side of the a membrane:

water highlow

Selectively permeable

OSMOSIS

• Hypertonic = __________________solute; _________________water

• Hypotonic = ____________________solute; _________________water

– Water always moves from ___________→ ______________

higher concentrationlower concentration

lower concentration

higher concentration

hypOtonic

hypertonic

OSMOSIS

• Isotonic = Relative concentrations of ______and ______ are ________

– There will be ___ net movement of water if two solutions are isotonic

water

solute equal

no

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAcQjRxqFQoTCPGX3qv-rcgCFcI9Pgod69kPWg&url=http://www.as.wvu.edu/~rbrundage/lecture6/sld009.htm&bvm=bv.104317490,d.dmo&psig=AFQjCNH_62v7WTlfiQ7Fm-SWRR8xfeb0vw&ust=1444225737941639

OSMOSIS

• Cells must have a mechanism for counteracting the pressure osmosis can create, otherwise a cell could swell & burst or explode when it is placed in a ___________ environment

• How to control Osmotic Pressure:o Cell wall - Rigid boundary found in ________________

o Physically prevents cell from expanding

o Contractile vacuole- Actively________ water out of cell single-celled organisms without ________

o Blood/Extracellular Fluid- is mostly water to equalize osmotic pressure. Designed to be __________ with cells.

hypotonic

pumpsCell walls

Plants, bacteria, fungi & some protists

isotonic

-Hypotonic; -cell will undergo cytolysis or lyse (the cell will burst)-This can kill the animal cell

-Hypertonic; -cell will crenate (the cell will shrivel up)-This causes cell to dehydrate and not function

-isotonic; -preferred cell state

-Hypertonic; -cell will undergo plasmolysis (cell membrane pulls away from cell wall)

-isotonic; -Cell does not mind being in this state; neither beneficial or harmful to the cell

-Hypotonic; -cells see increased turgor pressure-This is the preferred state for plant cells

ACTIVE TRANSPORT

Requires energy in the form of ATP

3 types:• Protein Pumps

• Endocytosis

• Exocytosis

PROTEIN PUMPS

Protein Pumps:

• 1. Protein Pumps –Energy-requiring process during which membrane proteins pump molecules across a membrane

____________________

from a ______concentration to a ________concentration.

concentration gradient

low

high

PROTEIN PUMPS

An example is the sodium-potassium pump. Its purpose is to establish an _____________gradient in cells by pumping __ sodium ions (__) out of the cell for every __ potassium ions (__) pumped into the cell. This slight ________charge inside the cell relative to the outside is very important for ________________

and _________________.

electrochemical

3 Na

2 Knegative

muscle contractions

Nerve impulses

ENDOCYTOSIS AND EXOCYTOSIS

Endocytosis: “cell eating or sucking”.

Larger substances are moved into the cell from the

exterior by extending the cell membrane, forming a

vesicle around the substance. Examples include

macrophages, amoeba, etc.

Exocytosis- “cell spitting ”. Export of molecules from the inside of the cell to the exterior of the cell by a vesicle fusing with the cell membrane. Mechanism used to release hormones from cells

ENDOCYTOSIS AND EXOCYTOSIS

ENDOCYTOSIS

Endocytosis

Exocytosis

https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAcQjRxqFQoTCITNytr6rcgCFUR7Pgod66sC4A&url=https://en.wikibooks.org/wiki/Structural_Biochemistry/Lipids/Membrane_Transport&psig=AFQjCNGdylXpelXviOrVz_MMteCheKdBww&ust=1444224771968156

Random movement of molecules in a liquid or gas

A. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump

Requires energy in the form of ATP

A. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump

cell sucking in or eating

A. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump

Diffusion of specific molecules through a protein channel

A. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump

Diffusion of water through a selectively permeable membrane

A. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump

Movement of molecules from high concentration to low, does NOT

require energyA. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump

Movement of ions and molecules against the concentration gradient,

requires energyA. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump

Cell spitting out or pooping

A. Active transport

B. Diffusion

C. Endocytosis

D. Exocytosis

E. Facilitated Diffusion

F. Osmosis

G. Passive Transport

H. Protein Pump