Biology Bio-Molecules Exam Study Guide
This review does not contain the questions on the test. This review contains the information you should understand in order to apply your
knowledge to the up-coming test questions. This knowledge should have been obtained from the activities, labs, lessons, and formative
assessments from this unit of study. If you are having trouble understanding any of this information, it is your responsibility to attend tutorials
from one of the Biology teachers before your summative exam.
1. Explain the pH scale below.
(Also label on the pH scale where you would find ‘very acidic’, ‘very basic/alkaline’, and ‘neutral’)
Acids
Neutral
Bases
2. What is the difference between an acid and a base?
Acids- high numbers of H+ ions
Bases- high numbers of OH- ions
3. Draw and label a single water molecule. Why is water considered ‘polar’?
Oxygen does not share it’s valence electrons evenly with Hydrogen (O has a higher electronegativity)
4. For each Bio-molecule below, give the monomer/subunit:
-carbohydrates: monosaccharide
-proteins: amino acid
-lipids: fatty acid
-nucleic acids: nucleotide
5. What are three commonalities between all 4 of the Biomolecules?
Polymers that are made of multiple monomers connected together, contain C H O, essential for life
6. Name the Bio-Molecule associated with each item below:
-hydrophobic (repels water): Lipids
-made entirely of sugar molecules: Carbohydrates
-contains a phosphate group: Nucleic Acids
-polypeptide: Proteins
7. You will be expected to recognize a visual of each Bio-Molecule. For each of the molecule pictures below, label the type
of Bio-Molecule AND explain WHY it belongs to that particular type of Bio-Molecule group.
A.
B.
C.
D.
Protein; Nitrogen present
in structure
Carbohydrate;
1:2:1 Ration of
C:H:O
Nucleic Acid; 3 parts:
Phosphate group, pentose
sugar and a NitrogenCarbon ring
Lipid; long chain with
many bonds (to store
loads of energy- ATP)
8. Explain the difference between the two chemical reactions below and the parts (reactants/products):
Reactants
Products
Products
Reactants
The first is a SYNTHESIS reaction (building/combining); Second is a DEGRADATION reaction (breaking down)
EX. Dehydration Synthesis
Hydrolysis
9. Using the picture to the right, explain how an enzyme works.
(Define ‘substrate’ and ‘active site’ in this explanation.)
An enzyme has an active site (LOCK) that is a specific shape and binds to specific compounds aka
Substrates (KEY) to speed up a chemical reaction (a CATALYST) by lowering the amount of energy needed to
Make the reaction occur.
10. What makes the different enzymes in living things ‘molecule specific’?
Specific shape of the active site on the enzyme
11. What are the five main functions of proteins? Give an example of each.
Communication: hormones like Insulin
Structure: protein channels in cell membrane
Defense: antibodies like Immunoglobulin
Act as a Catalyst: Enzymes to aid in chemical reactions
Repair and Maintenance: keratin and elastin that are present in hair and skin
12. What are the 3 components of a nucleotide?
Phosphate group (PO4)
Pentose Sugar (Deoxyribose; Ribose)
Nitrogen-Carbon ring (Adenine, Guanine, Cytosine, Thymine)
13. What element do nucleic acids and proteins contain that carbs and lipids do not?
NITROGEN!!!
14. Explain how energy is released from an ATP molecule.
Breaking of chemical bonds
(remember our pixie stick analogy)
Science vocabulary:
-monomer: single building block
-Polymer: multiple building blocks connected together
-element: one of a class of substances that cannot be separated into simpler substances by chemical means
-polarity: compounds that contain molecules of opposite charges that are bonded together (water)
-carbon skeleton: primary structure of a compound made of Carbon atoms
-peptide bond: bond between Amino Acids
-dehydration synthesis: loss of H2O molecule when monomers are combined
-triglyceride: lipid composed of 3 glycerol molecules
-hydrolysis: adding a H2O molecule to break down a polymer into monomers
-cholesterol: lipid that body uses to make sex hormones
-covalent bond: a chemical bond in which electron(s) are shared
-starch: complex carbohydrate (polysaccharide)
-Glycogen: polysaccharide that is stored in the muscles and liver of humans (energy reserves)
-ripen/ripening: chemical reaction (aided by enzymes) that results in the maturing of fruit/vegetables
Pre-AP
-Be familiar with the degrees of protein structure:
Primary (a simple chain of Amino Acids)
Secondary (helical or accordion fold)
α helix
Tertiary
β sheet
Quaternary (protein unit)
TEKS tested:
9: The student knows the significance of various molecules involved in metabolic processes and energy conversions that occur in living organisms.
The student is expected to:
A: compare the structures and functions of different types of biomolecules, including carbohydrates, lipids, proteins, and
Nucleic acids
C: identify and investigate the role of enzymes
D: analyze and evaluate the evidence regarding formation of simple organic molecules and their organization into long
Complex molecules having information such as the DNA molecule for self-replicating life.