Regents Review: Biochemistry
Define the following terms:
Biochemical Processes – chemical reactions that occur in organisms
Catalyst – speeds up the rate of a chemical reaction without being changed or used up
Enzyme – biological catalyst made from protein
pH – a measure of how acidic, basic or neutral a solution is based of [H +] and [OH-]
Synthesis – the combination of smaller subunits into complex molecules
Describe an atom versus an element versus a compound:
Atoms are composed of protons, neutrons and electrons. An element is made of the same type of atoms. A
compound is composed of two or more elements bonded together.
Write a chemical formula for an organic compound:
Glucose – C6H12O6
Compare organic versus inorganic compounds. Are there any exceptions?
Organic molecules contain carbon. Inorganic molecules do not contain carbon with the exception of CO 2
and CO3 that are considered inorganic.
What are the four types of organic molecules? What elements do they contain? What are their building
blocks? What is their overall shape? What is an example?
Molecule
Carbohydrate
Elements
CHO
Lipid
CHO
Protein
CHON
Building Block
Monosaccharide/Simple
Sugar
Glycerol and Fatty Acid
Chains
Amino Acids
Nucleic Acid
CHONP
Nucleotide
Shape
Hexagon
Head with two
tails
Spiral or pleated
ribbon
Helix or single
stranded
Examples
Glucose, starch,
glycogen
Fats, oils, waxes
Muscle, enzymes
DNA, RNA
What is an example of an organic chemical reaction that occurs within your body?
Glucose + Fructose  Sucrose
Glycerol + 2 Fatty Acid Chains  Phospholipid
Serine + Valine  Dipeptide
To speed up a reaction what can be added? It is used up during this reaction or remains unchanged?
A catalyst (enzyme) remains unchanged and is recycled after the reaction.
Name some biological processes:
Digestion of starch, synthesis of proteins (dehydration synthesis and hydrolysis)
Draw an enzyme and its corresponding substrate. Label the substrate, enzyme and active site:
Describe the lock-and-key model:
The substrate fits perfectly into the active site of the enzyme. The enzyme is specific to the shape of the
substrate.
Name some examples of enzymes in your body:
Lactase, catalase
What influences reaction rate:
Temperature, pH, concentration
What are coenzymes?
Enzymes that work together
Practice Regents Questions
1. The function of most proteins depends
primarily on the
(1) type and order of amino acids
(2) environment of the organism
(3) availability of starch molecules
(4) nutritional habits of the
organism
2. Chromosomes can be described as
(1) large molecules that have only
one function
(2) folded chains of bonded
glucose molecules
(3) reproductive cells composed of
molecular bases
(4) coiled strands of genetic
material
3. Enzyme molecules normally interact
with substrate molecules. Some
medicines work by blocking enzyme
activity in pathogens. These medicines
are effective because they
(1) are the same size as the
enzyme
(2) are the same size as the
substrate molecules
(3) have a shape that fits into the
enzyme
(4) have a shape that fits into all
cell receptors
4. The sweet taste of freshly picked corn
is due to the high sugar content in the
kernels. Enzyme action converts about
50% of the sugar to starch within one
day after picking. To preserve its
sweetness, the freshly picked corn is
immersed in boiling water for a few
minutes, and then
cooled.
Which statement most likely explains
why the boiled corn kernels remain
sweet?
(1) Boiling destroys sugar
molecules so they cannot be
converted to starch.
(2) Boiling kills a fungus on the
corn that is needed to convert
sugar to starch.
(3) Boiling activates the enzyme
that converts amino acids to
sugar.
(4) Boiling deactivates the enzyme
responsible for converting
sugar to starch.