Biochemistry WEB Practice
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. Which element would need to be removed from the molecule in Figure 6-2 to make it unsaturated?
Figure 6-2
a. carbon
b. hydrogen
____
____
____
____
____
____
____
____
____
____
c. oxygen
d. phosphorus
2. A single carbon atom can form a maximum of how many single covalent bonds?
a. 2
c. 6
4
b.
d. 8
3. In humans and other multicelluar organisms, which substance plays a central role as an energy source?
a. carbohydrate
c. protein
b. fat
d. water
4. Glycogen, used to store energy in the liver and muscle tissue, is an example of which type of molecule?
a. carbohydrate
c. saturated fatty acid
b. protein
d. steroid
5. Amino acids are the building blocks of which macromolecule?
a. carbohydrate
c. lipid
b. DNA
d. protein
6. An organism’s genetic information is stored in which type of macromolecule?
a. DNA
c. lipid
b. carbohydrate
d. protein
7. Which statement is true?
a. Simple sugars are made of polysaccharides.
b. Glycerol is made of fatty acids.
c. RNA molecules are made of nucleotides.
d. Amino acids are made of proteins.
8. Which of the following is NOT a carbohydrate?
a. enzyme
c. starch
b. sugar
d. glycogen
9. What are the monomers of nucleic acids?
a. peptides
c. saccharides
b. amino acids
d. nucleotides
10. Which is NOT an example of a lipid?
a. wax
c. ATP
b. steroid
d. oil
11. What determines the function of a protein?
a. Its amino acid sequence.
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____
____
c. How the amino acids react to each
other.
b. Its shape.
d. All of the above
12. Which of the following terms includes all of the others on the list?
a. monosaccharide
d. carbohydrate
b. disaccharide
e. polysaccharide
c. starch
13. The formula for glucose is C6H12O6. What would be the formula for a polysaccharide made from
10 glucose molecules bonded together.
a. C60H120O60
c. C60H102O51
b. C6H12O6
d. C60H100O50
14. Choose the pair of terms that correctly completes this sentence: Nucleotides are to
______________________ as ___________________ are to proteins.
a. nucleic acids, amino acids
c. genes, enzymes
b. amino acids, polypeptides
d. DNA, amino acids
Completion
Complete each statement.
15. The building blocks of lipids are
16. A reaction in which water is removed and two smaller products are yielded from a larger product is
called _______________________________.
17. A reaction in which a product, with the addition of water, is split into 2 reactants is called
_________________________
Short Answer
Figure 6-5
18. Classify A and B of Figure 6-5 as either saturated or unsaturated. Explain.
19. If carbs and lipids are both used for energy, how are they different?
20. What is cellulose? Describe its biochemistry.
Essay
21. A scientist discovers a new compound. He learns all about its chemical structure and function. He
names the newly found compound ambexidase. What can you describe about this compound’s
structure and function.
Biochemistry WEB Practice
Answer Section
MULTIPLE CHOICE
1. ANS: B
Two atoms of hydrogen would need to be removed.
Feedback
A
B
C
D
Removal of a carbon atom would break the chain.
Yes, removing hydrogen atoms would leave a double bond.
Oxygen atoms are not involved here.
There is no phosphorus in this molecule.
PTS: 1
TOP: 6-13
2. ANS: B
DIF:
Bloom's Level C
REF: 169
With four outer electrons, each unpaired, carbon can make four bonds.
Feedback
A
B
C
D
See page 166.
Correct.
It cannot make this many.
This is too many.
PTS: 1
TOP: 6-11
3. ANS: A
DIF:
Bloom's Level C
REF: 166
Carbohydrate is the key substance for energy metabolism. Fat is used for storage but not typically as a
direct energy source.
Feedback
A
B
C
D
Well done.
This is mostly for energy storage, not use.
This can be used for energy but that is not its main role.
Water does not provide energy, though it is essential for life.
PTS: 1
NAT: LS_5b
4. ANS: A
DIF: Bloom's Level C
STA: III.2.3
TOP: 6-13
Glycogen is made of glucose and is a carbohydrate.
Feedback
A
B
C
D
Correct.
See page 168.
Glycogen is not a fatty acid.
See page 168.
REF: 168
PTS: 1
NAT: LS_5b
5. ANS: D
DIF: Bloom's Level A
STA: III.2.3
TOP: 6-13
REF: 168–169
Amino acids are the building blocks of protein.
Feedback
A
B
C
D
Carbohydrates are made of sugar units.
DNA is made of nucleotides.
See page 170.
Correct.
PTS: 1
NAT: LS_5b
6. ANS: A
DIF: Bloom's Level B
STA: III.2.3
TOP: 6-12
REF: 170
DNA is the genetic material of the cell.
Feedback
A
B
C
D
7.
8.
9.
10.
11.
12.
13.
Correct.
This provides fuel.
See page 171.
Protein is not the substance used to store the genetic information.
PTS: 1
DIF: Bloom's Level A
REF: 171
NAT: LS_5b
STA: III.3.1
TOP: 6-13
ANS: C
PTS: 1
REF: p. 47
ANS: A
PTS: 1
ANS: D
PTS: 1
ANS: C
PTS: 1
ANS: D
PTS: 1
ANS: D
PTS: 1
ANS: C
Remember - for each bond you lose a water - so for 9 bonds you lose a total of 18 hydrogens and 9
oxygens.
PTS: 1
14. ANS: A
PTS:
1
SHORT ANSWER
15. ANS: fatty acids and glycerol.
PTS: 1
16. ANS: dehydration synthesis
PTS:
1
17. ANS: hydrolysis.
PTS: 1
18. ANS:
A is saturated because it contains only single bonds. B is unsaturated because it contains a double bond.
PTS: 1
DIF: Bloom's Level C
REF: 169
TOP: 6-12
20. ANS:
Cellulose is a carbohydrate. It is a polysaccharide, but it is not used for energy as most carbs are.
Instead it is used in the cell walls of plants for structural support.
PTS: 1
19. ANS:
Carbs are for immediate energy usage in the cells, where as lipids are used for energy storage and
need to be broken down before they can be used for energy. The lipids are store more energy than
the carbs.
PTS:
1
ESSAY
21. ANS:
The ending “ase” means that it is an enzyme. Since it is an enzyme, it is a protein made of amino
acids linked together by peptide bonds. Its shape determines the reaction that it can catalyze. It is
possible, though just a guess, that it may act on a sugar called ambexidose based on what we
learned about other enzymes working on sugars with similar names.
PTS:
1