Lecture Notes 3: Basic Biochemistry
Lecture Notes # 3
Biology A
Fall Term
Initials and Hour:______________
I. Basics of Chemistry
A. The Atom
1. ______________________________
2. Made of a __________________ surrounded by a
cloud of negative particles called ____________.
3. All elements are listed on the _____________.
4. Elements in the body:
Oxygen (65%)
Copper, Zinc, Selenium,
Carbon (18%)
Molybdenum, Fluorine, Chlorine,
Hydrogen (10%)
Iodine, Manganese, Cobalt, Iron
Nitrogen (3%)
(0.70%)
Calcium (1.5%)
Phosphorus (1.0%)
Lithium, Strontium, Aluminum,
Potassium (0.35%)
Silicon, Lead, Vanadium, Arsenic,
Sulfur (0.25%)
Bromine (trace amounts)
Sodium (0.15%)
Magnesium (0.05%)
Reference: H. A. Harper, V. W. Rodwell, P. A. Mayes, Review of
Physiological Chemistry, 16th ed., Lange Medical Publications, Los Altos,
California 1977.
B. Molecules
1. When two or more atoms join together, they form a
___________.
2. These are called _______________, and are based on
interactions between the _________.
3. If a bond joins different elements, the new substance
is a __________.
C. Types of Bonds
1. _____________
a. Electrons move from one atom to the other.
b. Atoms become positively or negatively
charged; called ____.
c. Charges attract or repel.
d. Good for __________________
2. _______________
a. Electrons are shared between two atoms.
b. Atoms must remain together
c. Bonds are flexible
d. Good for ________________.
3. _______________
a. Hydrogen holds electrons weakly
b. Has a slightly positive charge, attracted to
anything negative.
c. Creates weak bonds that help hold structures
but can be broken easily.
d. Examples: _________________
D. Molecules and Energy
1. Energy is stored in the bonds between atoms. Energy
is required to ______________ bonds.
2. The amount of energy varies with the type of bond.
Some bonds (hydrogen) are easily broken while others
(triple covalent) are very hard.
II. Water Chemistry
A. ________ is the most abundant chemical in the body.
B. Water has many characteristics that make it vital to our
bodies.
1. _____—water is a very small molecule, so it moves
fast and can squeeze into tiny crevasses between other
molecules.
2. _________--Hydrogen has a slightly positive charge
while oxygen has a slightly negative charge. This
makes it easy for water to pry apart other charged
molecules, dissolving them.Called a________________.
3. _______________--Due to polarity, water forms a
crystal structure that is less dense than liquid water.
4. _____________--water absorbs and releases heat
energy slowly, and can hold a great deal of heat energy.
This helps organisms maintain their body temperature in
the safe range.
5. __________________--Polarity allows water to stick
to itself (cohesion) and to any charged material
(adhesion). Water can glue materials together.
6. _______--Water can act as either an acid or a base,
maintaining a stable pH in our bodies.
III. Macromolecules
A. What are they?
1. __________________________________
_______________________________________
2. Made of smaller pieces called __________ that can
be assembled like legos to form a variety of structures.
A large chain of monomers is called a _________.
B. Carbohydrates
1. Monomer: ___________________________
2. Polymer: ____________________________
3. Structure:_____________________________
_______________________________________
4. Uses: _______________________________
5. Examples: ___________________________
C. Lipids
1. Monomer: ___________________________
2. Polymer: ____________________________
3. Structure:____________________________
_______________________________________
4. Uses: _______________________________
5. Examples: ___________________________
D. Protein
1. Monomer: ___________________________
2. Polymer: ____________________________
3. Structure:_____________________________
_______________________________________
4. Uses: _______________________________
5. Examples: ___________________________
E. Nucleic Acids
1. Monomer: ___________________________
2. Polymer: ____________________________
3. Structure:____________________________
_______________________________________
4. Uses: _______________________________
5. Examples: ___________________________
IV. ATP
A. ATP stands for _____________________
B. Cells use ATP as a __________________
C. Made of adenine with ___ phosphates
D. Lots of energy is stored in the bond between
_____________________________
E. When this bond is broken, tremendous energy is released.
F. The pieces are then reassembled, storing more energy for
another use.
V. Enzymes
A. Special proteins that speed chemical reactions
1. Chemical reactions require a certain
_______________ to get started.
2. Enzymes decrease this energy, making reactions
occur faster.
B. Lock-and-Key Model
1. Enzymes are not used up by the reaction, but each
can only work on one reaction (________________).
2. This is called the lock-and-key model of enzymes.
An enzyme is like a _____ which can open exactly one
_____. If you want to “unlock” another reaction, you
need a different enzyme.
C. Factors which affect enzymes
1. _____________--enzymes, like all proteins, change
shape when exposed to heat or cold. Each has an
optimal temperature range.
2. ____--all enzymes have an optimal range of pH.
Example: stomach
3. _____________--having more enzymes makes the
reaction faster.
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