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Unit 2- The Chemistry
of Life Notes
Learning Targets:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Identify elements common to living things.
Describe how ions work.
Compare ionic and covalent bonds
Recognize the importance of hydrogen bonding.
Explain why many compounds dissolve in water.
Compare acids and bases.
Describe the bonding properties of carbon atoms
Compare and understand the importance of the four macromolecules: carbohydrates,
lipids, proteins, and nucleic acids.
Describe how bonds break and reform during chemical reactions
Explain why and how chemical reactions release or absorb energy.
Explain the effect of catalysts on activation energy.
Describe and explain how enzymes regulate chemical reactions.
Unit Opener: Carnivorous plant= Venus flytrap
Like other carnivores, the Venus flytrap eats animals to get
nutrients that it needs to make molecules such as proteins and nucleic
acids. Other chemical compounds made by plant’s cells enable the
Venus flytrap to digest the animals that it eats. These chemicals are
similar to the chemicals that allow you to digest the food that you eat.
If plants can make their own food through photosynthesis, why
would a plant species evolve a mechanism to capture and eat
animals?
_____________________________________
_____________________________________
_____________________________________
Venus flytraps grow in swampy areas that have nitrogen poor soil.
These plants get the nitrogen they need for survival by trapping and
digesting animals.
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What is everything made up of?
 ______________________________________________
 ______________________________________________
Atoms are made up of:

___________________________________________________

___________________________________________________

___________________________________________________

___________________________________________________

___________________________________________________
Draw and Label the atom (A little review):
Atomic Mass=
Atomic Number=
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Elements
 ________________________________________________________
________________________________________________________
 ________________________________________________________
________________________________________________________
 ________________________________________________________
________________________________________________________
Atoms are made up of the same types of particles, so what makes one
element different from another?
_____________________________________________________________
_____________________________________________________________
How many protons does hydrogen have? Oxygen?
Energy Levels:
1.
______________________________________________________
______________________________________________________
2.
______________________________________________________
3.
______________________________________________________
4.
______________________________________________________
______________________________________________________
5.
______________________________________________________
6.
______________________________________________________
______________________________________________________
______________________________________________________
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4
______________________________________________________
______________________________________________________
______________________________________________________
Why does your blood need iron?
_____________________________________________________________
Why does your body need chromium?
_____________________________________________________________
_____________________________________________________________
Compounds:
1.
2.
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
Ions:
1. Atom that has gained or lost one or more electrons.
2.____________________________________________________________
_____________________________________________________________
_____________________________________________________________
3. Either positive or negative
4. Atoms with few electrons= lose electrons and becomes more positive
5.____________________________________________________________
NaCl
 Transfers electron from sodium atom to chlorine atom
___________________________________________________________
_____________________________________________________________
___________________________________________________________
_____________________________________________________________
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___________________________________________________________
_____________________________________________________________
Opposites attract (+ / -)
What determines whether an atom becomes a positive ion or a negative
ion?
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
Molecule:
_____________________________________________________________
_____________________________________________________________
Covalent Bonds
__________________________________________________________
___________________________________________________________
_____________________________________________________________
___________________________________________________________
_____________________________________________________________
CO2 Example
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
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Properties of Water!!!!!
Waters unique properties allow life to exist on
Earth.
Polar
Nonpolar
They both tend to remain separate that is why they say, “oil and water
don’t mix. “
Life depends on hydrogen bonds
 ________________________________________________________
________________________________________________________
________________________________________________________
 ________________________________________________________
________________________________________________________
________________________________________________________
 ________________________________________________________
________________________________________________________
 ________________________________________________________
________________________________________________________
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Properties of Hydrogen bonds
Weakest of the bonds
High specific heat= water resists changes in temperature; therefore
water must absorb more heat energy to increase temperature.
*Very important with cells because our cells release a lot of
heat and water absorbs that heat which allows us to regulate cell
temperatures.
Cohesion->
_____________________________________________________________
_____________________________________________________________
*Makes water molecules stick together.
*Ex- beads on a car when it is washed
*Spider walking on top of the water.
Adhesion->
_____________________________________________________________
_____________________________________________________________
*Water molecules stick to other things.
*Ex- upward curve of the surface of the
water-> graduated cylinder
*Ex- plants transport water up their
roots to their leaves.
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Many compounds dissolve in water – UNIVERSAL SOLVENT
Molecules and ions can’t take part in chemical processes inside cells
unless they dissolve in water.
Materials such as sugar and oxygen cannot be transported from one
part of an organism to another unless they are dissolved in blood, plant
sap, or water based fluids.
Solution=
_____________________________________________________________
_____________________________________________________________
Solvent
Solute
Solubility:
 ________________________________________________________
 ________________________________________________________
 ________________________________________________________
 ________________________________________________________
 ________________________________________________________
Your plasma (liquid part of your blood) is 95% water. Which is the solvent
and solute?
Water= ______________
Dissolved proteins, platelets, minerals, hormones= _____________
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Why do the solutes such as proteins and sugars dissolve in the water of
blood plasma?
_____________________________________________________________
_____________________________________________________________
Let’s Review a little!!!!! Questions????
1.
2.
3.
4.
5.
6.
Sum it up! Properties of Water:
1. Hydrogen Bonding- strong cohesion (insects walking on water)
2. Capillary Action- water moves upward (Roots to leaves)
3. Strong Adhesion- attraction between two unlike substances
4. Universal Solvent- dissolves everything
5. High Specific Heat- cools / heats up slowly to allow temperatures in
organisms to maintain homeostasis
6. Expands when freezes making it less dense
Acids and Bases
Acids
Bases
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How is Ph regulated in our bodies?
1.
2.
3.
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
Carbon Based Molecules
Carbons unique bonding properties
1.
2.
3.
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
______________________________________________________
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Carbon Chains and Rings- three fundamental features
Draw each one!
Straight Chain
Branched Chain
Ring
Monomer / Polymer
Polymer=
_____________________________________________________________
_____________________________________________________________
Monomer=____________________________________________________
Draw the picture and label
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Four Major Carbon Based Molecules / Macromolecules
1.
2.
3.
4.
Carbohydrates
___________________________________________________________
___________________________________________________________
___________________________________________________________
___________________________________________________________
_____________________________________________________________
Monosaccharides:
 ________________________________________________________
 ________________________________________________________
 Draw the molecule
Disaccharides
 ________________________________________________________
 ________________________________________________________
________________________________________________________
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 Ex- Sucrose= common table sugar (made from glucose and fructose)
 Ex- Lactose= milk sugar (made from glucose and galactose)
Polysaccharides
 ________________________________________________________
________________________________________________________
 ________________________________________________________
 Ex- starch and glycogen -> energy storage in plants and animals
 Ex- Cellulose- cell walls in plants
LIPIDS
Non-polar molecules because they are insoluble in water (they don’t
dissolve)
_____________________________________________________________
_____________________________________________________________
___________________________________________________________
Function_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
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Monomer=_______________________________
Polymer=_________________________________
3 Main Lipids:
1. Fats or Triglycerides ________________________________________________________
________________________________________________________
2. A. Saturated fatty acids= held together by a single covalent bond
and is solid at room temperature.
i. Has the maximum number of hydrogen atoms possible
B. Unsaturated fatty acids= one or more double bonds between the
carbon atoms.
-Not saturated with hydrogen atoms
C. Polyunsaturated =
_____________________________________________________________
_____________________________________________________________
3. Phospholipids ___________________________________________________
___________________________________________________
 ___________________________________________________
 ___________________________________________________
 ___________________________________________________
Proteins
 Most varied- a part of everything from moving your leg to digesting
your pizza.
 Protein is the
________________________________________________________
________________________________________________________
__________
 Amino acids are referred to as the
________________________________________________________
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________________________________________________________
__________
- We use 20 different amino acids to build proteins in our
bodies.
- Your body makes 12 and the others need to be ingested through
meat, beans, and nuts.
- All have similar structures: hydrogen atom, an amino group (NH2),
and a carboxyl group (COOH).
 ___________________________________________________
___________________________________________________
___________________________________________________
 ___________________________________________________
 ___________________________________________________
 ___________________________________________________
___________________________________________________
___________________________________________________
Draw the polypeptide chain and label.
- Held together by covalent bonds called peptide bonds. The bonds form
between the amino group of one amino acid and the carboxyl group of
another amino acid.
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 Polypeptide forms between two amino acids
 They are a single chain of three or more amino acids linked together
by peptide bonds.
Functions of Proteins
1. Catalyzing Enzymes________________________________________________________
i. ______________________________________________
ii. ______________________________________________
______________________________________________
iii. ______________________________________________
iv. ______________________________________________
v. ______________________________________________
______________________________________________
2. Defensive Proteins________________________________________________________
________________________________________________________
i. Ex-____________________________________________
ii. Ex-____________________________________________
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3. Storage Proteins________________________________________________________
________________________________________________________
4. Transport Proteins________________________________________________________
________________________________________________________
i. Ex-____________________________________________
ii. Ex-____________________________________________
5. Support Proteins________________________________________________________
i. Ex-____________________________________________
ii. Ex-____________________________________________
iii. Ex-____________________________________________
6. Motion Proteins________________________________________________________
________________________________________________________
7. Messenger Proteins________________________________________________________
________________________________________________________
i. Ex-___________________________________________
ii. Ex-___________________________________________
iii. Ex-____________________________________________
Nucleic Acids
 ________________________________________________________
________________________________________________________
 ________________________________________________________
 ________________________________________________________
 Nucleotides are made up
of_______________________________________________________
________________________________________________________
 Two types= ____________________________
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 ONE FUNCTION!!!!!->
________________________________________________________
________________________________________________________
________________________________________________________
 DNA is the basis of genes and heredity.
Chemical Reactions
 ________________________________________________________
________________________________________________________
________________________________________________________
Write the equation for cellular respiration and label the reactants and
products.
What causes bonds in oxygen and glucose molecules to break?
What causes bonds in oxygen and glucose molecules to break?
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
What happens when new bonds form in carbon dioxide and water?
 When new bonds form, energy is released and this energy that is
released is equal to the amount of energy that breaks the same
bond.
 Sometimes bonds can form a chemical equilibrium, meaning they are
reversible and the same on both sides of the equation.
 Ex- Blood cells and plasma transport materials throughout the body.
Carbonic acid dissolves in the blood so that carbon dioxide can be
transported to the lungs.
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Chemical reactions release or absorb energy
1.____________________________________________________________
2.____________________________________________________________
3.____________________________________________________________
Activation Energy
 ________________________________________________________
________________________________________________________
 ________________________________________________________
________________________________________________________
Exothermic
 ________________________________________________________
 ________________________________________________________
________________________________________________________
 ________________________________________________________
 Ex- firefly squid, fireflies, cellular respiration (releases usable
energy as well as keep your body warm).
 Endothermic
 ________________________________________________________
 ________________________________________________________
 Example- photosynthesis-> plants absorb energy from the sun and
use that energy to make simple and complex carbohydrates.
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Enzymes!!!!!
How did the Venus flytrap digest the frog?
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
 Break down food into smaller molecules that the body can use.
What is activation energy?
_____________________________________________________________
 Most of the time the activation energy for a chemical reaction
comes from a _________________________________ sometimes
the process is very slow.
 In order to speed the process up substances called
________________________________________________________
_______________________________________________________
 When a catalyst (ex- enzymes) is present less energy is needed and
products form a lot __________________.
What are two functions of catalysts in chemical reactions?
1.
2.
Enzymes:
 Definition=
________________________________________________________
________________________________________________________
 Reactants are usually found at very low concentrations in the body,
but really need to occur quickly.
 ________________________________________________________
________________________________________________________
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 _______________________________________________________
 Temperature, concentration, and ph can affect the shape, function,
rate, and activity of the enzyme.
 ________________________________________________________
 If temperature is a little elevated then the hydrogen bonds will fall
apart, the enzyme structure will change, and its ability to function
will be lost.
 This is the reason why a high temperature / fever is very dangerous
to a person.
 Examples:
 1._______________________________________________________
________________________________________________________
 2._______________________________________________________
________________________________________________________
 The structure is so important because
________________________________________________________
________________________________________________________
________________________________________________________
 Specific reactant an enzyme acts on are called
________________________
 The sites where substrates bind to enzymes are called
________________________.
 Enzymes bring substrate molecules close together, then they
decrease activation energy, substrates attach together and their
bonds are weakened, and then the catalyzed reaction forms a
product that is released from the enzyme.
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Reflection
On a sheet of paper, review the three parts of the lock and key model and
write a paragraph (3-5 sentences) describing the analogy. Consider why the
model is described as a lock and key. Also identify the different parts and
what happens to each part after the reaction is complete. You may use
your notes only as a guide.