unit 02 the chemical basis of life 2.1 introduction
TRANSCRIPT
Unit 02
The Chemical Basis of Life
2.1 Introduction
2.1: Introduction
What do you think of when you hear the word chemistry?
Think and Share
2.1: Introduction Write
• Chemistry• The composition of matter and how it
changes.
2.2 Structure of Matter
2.2: Structure of Matter Write
• Matter• Anything that has mass and takes up space
• Mass –• A measure of how much matter is in an
object• Volume
• The amount of space taken up by matter
2.2: Structure of Matter
2.2: Structure of Matter Write
•Density• Ratio of Mass and Volume
Which box has more density?
2.2: Structure of Matter
Which cube is more dense?
2.2: Structure of Matter
2.2 Structure of MatterElements and Atoms
2.2: Structure of Matter Elements and Atoms Write
•Element• Any material that can’t be broken down
into a more fundamental substance
2.2: Structure of Matter Elements and Atoms
2.2: Structure of Matter Elements and Atoms Read
•There are 118 known elements
•20 of these elements make up the human body
2.2: Structure of Matter Elements and Atoms Read
Elements in the Human Body
I am mostly made up of….
2.2: Structure of Matter Elements and Atoms
2.2: Structure of Matter Elements and Atoms Read
• The type of element is determined by the type of atom.
• Do you remember the structure of an atom?
Draw an Atom
2.2: Structure of Matter Atomic Structure
2.2: Structure of Matter Elements and Atoms Write
•Atom• The basic unit of matter• The type of atom determines the type of
element
2.2 Structure of MatterAtomic Structure
2.2: Structure of Matter Atomic Structure Read
•An atom is composed of three particles
Proton (+) Neutron (N) Electron (e-)
0
2.2: Structure of Matter Atomic Structure Write
•Proton• Subatomic particle with a positive (+)
charge
•Neutron • Subatomic Particle with no charge (N)
•Electron• Subatomic Particle with a negative charge
(-)
•Nucleus• Center of an atom• Made up of Protons and Neutrons• Contains most of the mass
N0
2.2: Structure of Matter Atomic Structure Write
P+
N0 P+
P+ N0
Nucleus
•Electron Shell• An orbit around the nucleus• Electrons can be found on electron shells
• Electrons on the outermost electron shell are called valence electrons
N0
2.2: Structure of Matter Atomic Structure Write and draw
P+
N0 P+
P+ N0
Valence Electron
Normal electron
Electron Shells
e-
e- e-
•Each electron shell can hold a certain amount of electrons
• 1st electron shell = 2 electrons• 2nd electron shell = 8 electrons• 3rd electron shell = 8 electrons
2.2: Structure of Matter Atomic Structure Write and draw
e- e-
e- e-
e- e-
e-
e-
e-
e-e-
e- e-
e- e-
e- e-e-
1st2nd 3rd
Label the Parts of an Atom
N0 P+
N0 P+
P+ N0
e-
e- e-
Practice2.2: Structure of Matter Atomic Structure
2.2: Structure of Matter Atomic Structure Write
•Balanced Atom• Protons = Neutron = Electron
• Isotope• Protons = Electrons
• More or less Neutrons than protons
• Ion• Protons = Neutrons
• More or less electrons than protons• Creates a positive or negative charge
Medical Isotopes Video
• https://www.youtube.com/watch?v=QI6lFbCj4gQ
2.2: Structure of Matter Atomic Structure Watch
Isotope Video
• Radioactive tracers:• https://www.youtube.com/watch?v=GHLBcCv4rqk
• Isotopes:• https://www.youtube.com/watch?v=cKJMk2Oiod0
2.2: Structure of Matter Atomic Structure Watch
Element Name
Atomic Number (Number of Protons)
Element Symbol
Atomic Mass (Avg. Weight)
Write
2.2: Structure of Matter Elements and Atoms Practice
2.2: Structure of Matter Atomic Structure Write
•The type of atom is determined by the Atomic Number (# of protons)
P+
e-
Protons = 1Neutrons = 0Electrons = 1
Circle the element this atom will make.Write the element name under the atom.
2.2: Structure of Matter Atomic Structure
Protons = 2Neutrons = 2Electrons = 2
P+
e-
N0e
-
P+
N0
Circle the element this atom will make.Write the element name under the atom.
2.2: Structure of Matter Atomic Structure
Protons = 6Neutrons = 6Electrons = 6
P+
e-
N0
e-
P+
N0N
0
P+
e-
N0
P+
e-
e-
e- P
+
P+
N0
N0
Circle the element this atom will make.Write the element name under the atom.
2.2: Structure of Matter Atomic Structure
Protons = 8Neutrons = 8Electrons = 8
P+
e-
e-
P+ N
0N0
P+
e-
N0
P+
e-
e-
e-
P+
P+
N0
N0N
0
e-
P+
N0N0
P+
e-
e-
e-
Circle the element this atom will make.Write the element name under the atom.
2.2: Structure of Matter Atomic Structure
2.2: Structure of Matter Atomic Structure
2.2: Structure of Matter Atomic Structure Write
•Mass Number• The weight of the atom
• Proton mass + Neutron Mass• Electrons have very little mass so we don’t
count them• Not on periodic table of elements
Write2.2: Structure of Matter Atomic Structure
Write
Formulas:
To find protons Look at the Atomic number
To find Neutrons mass number - atomic number
To find electrons electrons = charge - protons
12
(1 – 11 = -10)
Protons:___________
Neutrons:__________
Electrons:___________
Protons:___________
Neutrons:__________
Electrons:___________
Protons:___________
Neutrons:__________
Electrons:___________
2.2: Structure of Matter Atomic Structure Practice
15 protons, 16 neutrons, and 18 electrons __________
56 protons, 82 neutrons, and 54 electrons _________
13 protons, 14 neutrons, and 10 electrons __________
2.2: Structure of Matter Atomic Structure
Draw the Isotopic Symbol for the following
P
Ba
Al
Atomic # = ProtonsMass # = Protons + NeutronsCharge = Protons - Electrons
Practice
2.2 Structure of MatterBonding of Atoms + Molecules and Compounds
Write
2.2: Structure of Matter Bonding of Atoms Write
•Chemical Bonding• an attraction between atoms that causes
them to bind and create molecules
2.2: Structure of Matter Bonding of Atoms Write
•Molecule• Two or more atoms joined together
chemically
•Compound• A molecule that contains at least two
different elements.
Molecule
Compound
Compounds are a type of molecule.
All compounds are molecules but not all molecules are compounds.
2.1: Structure of Matter Molecules and Compounds Write
2.2: Structure of Matter Bonding of Atoms Write
Why does chemical bonding occur?
• Every atom wants its outer electron shell full of electrons. This is why bonding between atoms occurs.
e- e-
e- e-
e- e-
e-
e-
e-
e-
e-
e- e-
e- e-
e- e-
e- e-
e-
e-
e-
e-
2.2: Structure of Matter Bonding of Atoms Write
•Octet Rule• atoms create chemical bonds to achieve an
octet (8) of electrons in their outer most electron shell
2.2: Structure of Matter Bonding of Atoms Write
•Two ways to obtain an octet:
• Ionization • Transfer of electrons
• Sharing
2.2: Structure of Matter Bonding of Atoms Write
• Ionization• Occurs when an atom gives away or
receives an electron causing it to turn into an ion.
Cl17
Na11
-
+
Ionization: How atoms become IonsNa is going to donate an electron to Cl. This fills Cl’s energy level and drops Na back to a full energy level.
Because of the number of electrons is no longer the same as the protons there is a negative and positive charge.
Read and Watch
Watch
Ionic Bond
Transfering electrons creates ions. Oppositely charged ions are attracted to one another (opposites attract). This attraction is an ionic bond.
Read and Watch
Covalent Bonds
Read and Watch
• Sharing Electrons. Both atoms obtain 8 electrons in their outer electron shell.
Chemical Bond Video
• http://chemistry.about.com/od/chemicalbonding/a/chemicalbonds.htm
2.2: Structure of Matter Bonding of Atoms
Watch
Watch
2.2: Structure of Matter Bonding of Atoms Write
•Two types of Covalent Bonds:
• Non-polar Covalent Bonds• Electrons are shared equally• Results in a non-polar molecule
• Molecule does not have poles
• Polar Covalent Bonds• Electrons are shared unequally• Results in a polar molecule
• Molecules have positive and negative poles
Let’s Make Water
O
HH
Watch
O
H HPositive Pole
Negative Pole
Watch
Listen
Polar Molecules Non-Polar MoleculesListen
2.1: Introduction Write
•Polar Molecule• A molecule that has positive and negative
poles due to uneven sharing of electrons. Created by polar covalent bonds.
•Nonpolar Molecules• A molecule that is neutral. Created by
nonpolar covalent bonds.
Hydrogen Bond
Read and Watch
• A bond formed between two polar molecules. A positive pole is attracted to a negative pole.
Listen
2.2: Structure of Matter Bonding of Atoms Write
Ionic Bond Covalent Bond
Hydrogen Bond
One atom transfers (gives or takes) an electron to fill its outer energy level (ionization). The ions created from this transfer attract and form an ionic bond.
Two atoms share electrons to fill their electron shells
Two polar molecules bond together due to +/- charges
Three Types of Chemical Bonds
2.2 Structure of MatterFormulas
2.1: Structure of Matter Formulas Write
• Molecular Formula• Represents the numbers and types of
atoms in a molecule
H2O
CO2
O2
HCO3-
Ca+2CO3
-2
C6H12O6
Cl-
Mg+2K+
Na+
SO4-2
CO3-2
2.1: Structure of Matter Formulas Write
Number of Elements
Overall Charge
2.1: Structure of Matter Formulas Write
•Structural Formulas• Represents how the atoms are bonded
together• 1 bond 2 bonds
• 3 Bonds 4 Bonds
N N
2.1: Structure of Matter Formulas Write
2.2 Structure of MatterChemical Reactions
2.1: Structure of Matter Chemical Reactions Write
•Chemical Reactions• The rearrangement of atoms from one
arrangement to another.
•Law of Conservation of Mass• matter is not created nor destroyed during
a chemical reaction.
6H2O6CO26O2C6H12O6 + + + ATP + Heat
WaterCarbon Dioxide
OxygenGlucose + + + ATP + Heat
Write
•Chemical Formula• a representation of a chemical
reaction Reactants Products
6H2O6CO26O2C6H12O6 + + + ATP + Heat(aq)
2.1: Structure of Matter Chemical Reactions
2.1: Structure of Matter Chemical Reactions Write
Types of chemical reactions
• Synthesis: A + B AB
• Decomposition: AB A + B
• Exchange Reaction: AB + CD AD + CB
• Reversible Reaction: A + B AB
2.1: Structure of Matter Chemical Reactions Write
•Exothermic Reactions• a chemical reaction that releases
energy by light or heat.• Example: Aerobic Respiration
2.1: Structure of Matter Chemical Reactions Write
•Endothermic Reactions• Chemical reaction that absorbs heat or light
• Example: Photosynthesis
WaterCarbon Dioxide OxygenGlucose + + + ATP+
6H2O6CO2 6O2C6H12O6 + + ATP+Sunlight+
Sunlight
2.1: Structure of Matter Chemical Reactions Write
•Activation Energy• minimum energy required for a chemical
reaction to occur• All chemical reactions have an activation
energy.
•Catalyst• Particular atoms or molecules (usually an enzyme) that
can change the rate of a reaction by lowering the activation energy
Activation Energy
Energy
Energy Needed to Break bonds
Lactase Enzyme
GLU GAL
GLU GAL
Lactose
Lactose
2.1: Structure of Matter Chemical Reactions
2.1: Structure of Matter Chemical Reactions Write
2.2 Structure of MatterAcids and Bases
2.1: Structure of Matter Acids and Bases Write
•Solution• Solute + Solvent
• Solute: Substance that is dissolved• Solvent: Substance that dissolves the solute (usually water)
• Some compounds release ions when they dissolve in water.
• NaCl Na+ + Cl-
2.1: Structure of Matter Acids and Bases Write
•Electrolytes• Solutions that contain electrically charged particles (ions)
and will conduct an electric current• Acids and bases are examples of electrolytes
Hydroxide Ion (OH-)
Hydronium Ion(H3O+)
2.1: Structure of Matter Acids and Bases Write
•Acids• Electrolytes that release (donate) hydrogen
ions (H+)• HCL (hydrochloric acid) H+ + Cl-
•Bases• Electrolytes that release hydroxide ions
(OH-)• NaOH (sodium hydroxide) Na+ + OH-
2.1: Structure of Matter Acids and Bases Write
•pH• Measure of the the hydrogen ion
concentration in a solution
Acid Base
2.1: Structure of Matter Acids and Bases Write
• pH Scale• pH<7 = acidic (0-6)• pH = 7 = neutral (7)• pH > 7 = Basic (8-14)
Organ, fluid or membrane pH Function of pH
(1) Skin Natural pH is between 4 and 6.5 Barrier protection from microbes
(2) Urine 4.6 to 8.0 Limit overgrowth of microbes
(3) Gastric 1.35 to 3.5 Break down protein
(4) Bile 7.6 to 8.8 Neutralize stomach acid, aid in digestion
(5) Pancreatic fluid 8.8 Neutralize stomach acid, aid in digestion
(6) Vaginal fluid <4.7 Limit overgrowth of opportunistic microbes
(7) Cerebrospinal fluid 7.3 Bathes the exterior of the brain
(8) Intracellular fluid 6.0–7.2 Due to acid production in cells
(9) Serum venous 7.35 Tightly regulated
(10) Serum arterial 7.4 Tightly regulated
2.1: Structure of Matter Formulas
2.1: Structure of Matter Acids and Bases Write
•pH indicator• Anything that reacts to an acid or base by
changing color
Litmus Paper
Red Cabbage solution
Hydrangeas
http://www.shape.com/healthy-eating/diet-tips/alkaline-diet-real-deal
2.1: Structure of Matter Acids and Bases Write
http://www.shape.com/healthy-eating/diet-tips/alkaline-diet-real-deal
http://www.today.com/health/i-tried-alkaline-diet-what-its-summers-hottest-cleanse-trend-t37516
2.3 Chemical Constituents of Cells
NZSRU
2.1: Structure of Matter Formulas Write
•Organic Compounds• Contain both Carbon and Hydrogen
• Inorganic Compounds• Do not contain Carbon and Hydrogen
2.3 Chemical Constituents of CellsInorganic Substances
2.1: Structure of Matter Formulas Write
• Inorganic Substances• Water (H2O)
• Solvent• Most metabolic reactions occur in water
• Oxygen (O2)• Needed for cellular respiration
• Carbon Dioxide (CO2)• Waste
• Salts• Provide ions • Used for:
• Metabolic processes• Transport• Muscle contraction• Nerve impulse conduction
2.3 Chemical Constituents of CellsOrganic Substances
2.1: Structure of Matter Formulas Write
•Carbohydrates•Proteins•Nucleic Acids•Lipids
2.1: Structure of Matter Formulas Write
•Monomer• One thing
•Polymer• Many things
• A polymer is made up of many monomers.
Monomer Polymer
H
H
H
H
H
C
CH
OH
HO
C
OH
C OO
C
H
H
CH
CH
H
H
H
H
HO
H
C
CCH
OH
HO
C
OH
CO OH
O
Dehydration Synthesis
CH
H
H
H
H
HO
H
C
CCH
OH
HO
C
OH
CO O
H
H
H
H
H
H
C
CH
OH
HO
C
OH
C OO
C
H
H
C
HO
Hydrolysis
2.1: Structure of Matter Formulas Write
•Dehydration Synthesis• Combining two monomers by taking
out a water
•Hydrolysis• Breaking apart two monomers by inserting
a water
Which is which?Dehydration Synthesis
Hydrolysis
2.1: Structure of Matter Formulas Write
•Carbohydrates• Common Name: Carbs or Sugars• Elements Present: CHO• Uses By Living Things: Energy and Structure
2.1: Structure of Matter Formulas Write
•Carbohydrates• Monomer: Monosaccharide• Polymer: Polysaccharide
• Example• Starch
• Breads• Glycogen
• Energy storage in your muscles• Cellulose
• Gives plants their structure• Chitin
• Exoskeleton of insects
Monosaccharide Polysaccharide
2.1: Structure of Matter Formulas Write
•Proteins• Common Name: Protein• Elements Present: CHON• Uses By Living Things: Structure, Transport, Communication,
Enzymes
2.1: Structure of Matter Formulas Write
•Proteins• Monomer: Amino Acid• Polymer: Polypeptide or protein
• Example• Cell Receptors
• Cellular communication• Antibodies
• Immune system• Enzymes
• Catalyze chemical reactions
Amino Acid Polypeptide or Protein
2.1: Structure of Matter Formulas Write
•Nucleic Acid• Common Name: DNA and RNA• Elements Present: CHONP• Uses By Living Things: Information
Storage and Transfer
2.1: Structure of Matter Formulas Listen
•Nucleic Acid• Monomer: Nucleotide• Polymer: Nucleic Acid
• Example• DNA • RNA
Nucleotide
Poly
nucl
eotid
e or
Nuc
leic
Aci
d
2.1: Structure of Matter Formulas Write
•Nucleic Acid• Monomer: Nucleotide• Polymer: Nucleic Acid
• Example• DNA • RNA
Nucleotide
Poly
nucl
eotid
e or
Nuc
leic
Aci
d
2.1: Structure of Matter Formulas Write
•Nucleic Acid• Monomer: Nucleotide• Polymer: Nucleic Acid
• Example• DNA • RNA
Nucleotide
Poly
nucl
eotid
e or
Nuc
leic
Aci
d
2.1: Structure of Matter Formulas Write
•Lipids• Common Name: Fat• Elements Present: CHO• Uses By Living Things: Energy Storage
and Insulation
2.1: Structure of Matter Formulas Write
•Lipid• Lipids are not macromolecules• But they are still made up of parts
• 1. Glycerol Head• 2. Fatty Acid Chains
• Example• Triglycerides• Phospholipids• Testosterone and Estrogen
Glycerol
2.1: Structure of Matter Formulas Write
Glycerol
Triglyceride Phospholipid
Steroids From left to right: Cholesterol, Testosterone, and Estrogen
Functional Group
Structural Formula
Name of Compounds
Characteristics Draw an Example
Hydroxyl OH Alcohols Name ends in –ol
• Polar• Can form hydrogen
bonds
CarbonylC = O
Ketones • Soluble in water• Found in sugars
Carboxyl COOH Acids like vinegar (acetic acid)
• Polar• Soluble in water• acidic
Amine NH2 Amino Acids • Polar• Soluble in Water
Sulfahydryl SH Amino Acids • Stabilize protein structure
Phosphate PO4 ATP, DNA and RNA • Polar• Important in cellular
energy storage and transfer
Methyl CH3 Methylated Compounds
• Nonpolar• Important in
epigenetics
CC
O O
CCO O
O HOH
O H
NH
HN
H
H
S HSH
OO O-
O-
P
OH
CH
H
H
CH
HH