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Chapter 5
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) Which of these classes of biological molecules does NOT include polymers?
A) carbohydrates
B) lipids
C) nucleic acids
D) proteins
2) Molecules with which functional groups may form polymers via dehydration reactions?
A) carbonyl groups
B) carboxyl groups
C) either carbonyl or carboxyl groups
D) hydroxyl groups
E) either hydroxyl or carboxyl groups
3) Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?
A) Dehydration reactions eliminate water from lipid membranes, and hydrolysis makes lipid membranes
water permeable.
B) Hydrolysis creates monomers, and dehydration reactions break down polymers.
C) Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.
D) Dehydration reactions ionize water molecules and add hydroxyl groups to polymers; hydrolysis reactions
release hydroxyl groups from polymers.
E) Dehydration reactions can occur only after hydrolysis.
4) On food packages, to what does the term insoluble fiber refer?
A) starch
B) amylopectin
C) polypeptides
D) cellulose
E) chitin
5) Which of the following is true of both starch and cellulose?
A) They are both used for energy storage in plants.
B) They are both polymers of glucose.
C) They are both structural components of the plant cell wall.
D) They are cis-trans isomers of each other.
E) They can both be digested by humans.
6) The molecular formula for glucose is C6 H12O6 . What would be the molecular formula for a molecule made by
linking three glucose molecules together by dehydration reactions?
A) C18H32O16
B) C18H36O18
C) C6 H10O5
D) C18H30O15
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7) Which level of protein structure do the α helix and the β pleated sheet represent?
A) secondary
B) quaternary
C) primary
D) primary, secondary, tertiary, and quaternary
E) tertiary
8) What is the term used for a protein molecule that assists in the proper folding of other proteins?
A) chaperonin
B) enzyme protein
C) tertiary protein
D) renaturing protein
E) denaturing protein
9) One of the primary functions of RNA molecules is to
A) act as a pattern or blueprint to form DNA.
B) transmit genetic information to offspring.
C) function in the synthesis of proteins.
D) make a copy of itself, thus ensuring genetic continuity.
E) form the genes of higher organisms.
10) Which of the following descriptions best fits the class of molecules known as nucleotides?
A) a pentose sugar and a purine or pyrimidine
B) a nitrogenous base and a pentose sugar
C) a nitrogenous base, a phosphate group, and a pentose sugar
D) a phosphate group and an adenine or uracil
E) a nitrogenous base and a phosphate group
11) Which of the following are nitrogenous bases of the purine type?
A) adenine and thymine
B) uracil and cytosine
C) guanine and adenine
D) cytosine and guanine
E) thymine and uracil
12) Which of the following is an example of hydrolysis?
A) the synthesis of a nucleotide from a phosphate, a pentose sugar, and a nitrogenous base with the
production of a molecule of water
B) the reaction of a fat, forming glycerol and fatty acids with the release of water
C) the reaction of a fat, forming glycerol and fatty acids with the consumption of water
D) the synthesis of two amino acids, forming a peptide with the release of water
E) the reaction of two monosaccharides, forming a disaccharide with the release of water
13) The tertiary structure of a protein is the _____.
A) organization of a polypeptide chain into an α-helix or β-pleated sheet
B) overall protein structure resulting from the aggregation of two or more polypeptide subunits
C) order in which amino acids are joined in a polypeptide chain
D) unique three-dimensional shape of the fully folded polypeptide
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14) Steroids are considered to be lipids because they _____.
A) are not soluble in water
B) are made of fatty acids
C) are essential components of cell membranes
D) contribute to atherosclerosis
15) A glycosidic linkage is analogous to which of the following in proteins?
A) a disulfide bond
B) a β-pleated sheet
C) a peptide bond
D) an amino group
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