Biology 241 – Lecture
Chapter 2 (Chemical Level of Organization)
Practice Quiz
I. Circle the letter preceding the one best answer to each question:
1. Chose the one TRUE statement:
A. A pH of 7.5 is more acidic than a pH of 6.5 B. Anabolism consists of a variety of decomposition reactions.
C. An atom such as Cl, with seven electrons in its outer orbit, is likely to be an electron donor ( rather than
an electron acceptor) in ionic bond formation.
D. Polyunsatruated fats are more likely to reduce cholesterol level than saturated fats are.
2. Which of the following describes the structure of a nucleotide?
A. Base – base B. Phosphate – sugar – base C. Enzyme
D. Depeptide
E. Adenine – ribose
3. Which of the following groups of chemicals includes only polysaccharides?
A. Glycogen, starch
B. Glycogen, glucose, galactose
C. Glucose, fructose
D. RNA, DNA
E. Sucrose, polypeptide
4. C6H12O6 is the chemical formula for
A. an amino acid. B. a fatty acid.
C. a 6-carbon monosaccharide
D. a polysaccharide. E. ribose.
5. All of the following consist of organic chemicals correctly paired with their example except:
A. Nucleic acids: DNA and RNA
B. Lipids: triglycerides and phospholipids
C. Carbohydrates: glucose and sucrose D. Proteins: starch and ATP
6. Which of the following is a component of DNA but not of RNA?
A. Adenine
B. Phosphate
C. Guanine
D. Ribose
E. Thymine
II. Circle T (True) or F (False). If the statement is false, cross out the word(s) that make it false
and write in an appropriate correction so that the statement now becomes a true statement.
T F 7. K+ and Cl- are both cations.
T F 8. ATP is a molecule that contains more energy than ADP.
T F 9. Gastric juice, lemon juice, grapefruit juice, tomato juice, and coffee all have pH less than 7.0.
T F 10. The number of protons in an atom always equals the number of neutrons in that atom.
III. Using the blanks provided, fill-in the word or phrase that best fits the description given:
_____________________________11. This is the specific type of reaction in which a disaccharide is digested
to form two monosaccharides.
_____________________________12. Oxygen, water, carbon dioxide, and NaCl all belong to this division of
chemical substances.
_____________________________13. This is the number of different amino acids from which all human
proteins are formed.
_____________________________14. An element’s atomic number is equal to the number of this type of
subatomic particle in an atom of the given element.
_____________________________15. Fill in the names for the elements whose symbols are C,
_____________________________Ca, _________________________ K, __________________________ N
_____________________________Na, __________________________P, __________________________Mg
Biology 241 – Lecture
Chapter 2: Practice Quiz – continued
Page Two
IV. Of the choices given in parentheses, circle the correct answer; or fill-in the blank provided:
16. Chemically, enzymes consist mostly of (carbohydrates / lipids / proteins). Each enzyme reacts with a
specific molecule called a (reactant / substrate / product).
17. Names of most enzymes end in the letters (-ase / -ose / -use). Enzyme names also give clues about their
functions. For example, enzymes that remove hydrogen are called______________________________.
Anhydrases remove a ______molecule from reactants; lipases are enzymes that break down ____________;
lactose intolerance involves a deficiency of the enzyme _____________________.
Cofactors are (ions / proteins / vitamins), whereas coenzymes are _____________________. How do cofactors affect enzymes?
18. In DNA, bases are paired _____________ to _____________ and _____________ to _____________.
(give entire name)
(give entire name)
(give entire name)
(give entire name)
The first complementary base pair you listed is held together via _________ hydrogen bonds; and the
second complementary base pair you listed is held together via _________ hydrogen bonds.
19. DNA molecules differ from one another by their sequence of __________________. Note that bases form
the “rungs” of the DNA “ladder”. One gene is formed from about (10 / 100 / 1,000 / 100,000) rungs. Humans have about (20 / 200 / 2,000 / 20,000 ) functional genes, such as genes controlling ear lobe shape or
blood type. Genes regulate sequencing of amino acids that form body (carbohydrates / lipids / proteins).
20. ATP stands for __________________________________. When the terminal phosphate is broken, a great
deal of energy is released as the ATP molecules is split into __________________ + ________________.
21. The anaerobic phase of cellular respiration yields a net of ______ molecules of ATP; whereas the aerobic
phase yields a net of __________ molecules of ATP.