Bio 102 5
98) Which of the following molecules has (have) a functional group that frequently is involved in maintaining the tertiary structure of a protein?
A) 2
68) Which of the following best describes the flow of information in eukaryotic cells?
A) DNA → RNA → proteins
4) For this pair of items, choose the option that best describes their relationship. (A) The probability that amino acids with nonpolar side chains are hydrophobic. (B) The probability that amino acids with side chains containing a carboxyl group are hydrophobic.
A) Item (A) is greater than item (B).
5) For this pair of items, choose the option that best describes their relationship. (A) The number of purines in the DNA strand 5ʹ-AAGAGGAGAAA-3ʹ (B) The number of pyrimidines in the DNA strand 5ʹ-AAGAGGAGAAA-3ʹ
A) Item (A) is greater than item (B).
19) Which of the following is true of both starch and cellulose?
A) They are both polymers of glucose.
24) Which of the following statements is false for the class of biological molecules known as lipids?
A) They are soluble in water.
61) Roger Kornberg used this method for elucidating the structure of RNA polymerase.
A) X-ray crystallography
30) Large organic molecules are usually assembled by polymerization of a few kinds of simple subunits. Which of the following is an exception to this statement?
A) a steroid
13) On food packages, to what does the term ʺinsoluble fiberʺ refer?
A) cellulose
6) Which of the following is not a polymer?
A) glucose
12) The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are the α form. Which of the following could amylase break down?
A) glycogen
18) All of the following are polysaccharides except
A) glycogen
15) If 2 molecules of the general type shown in Figure 5.1 were linked together, carbon 1 of one molecule to carbon 4 of the other, the single molecule that would result would be
A) maltose.
47) Which bonds are created during the formation of the primary structure of a protein?
A) peptide bonds
38) The bonding of two amino acid molecules to form a larger molecule requires which of the following?
A) removal of a water molecule
52) Figure 5.7 best illustrates the
A) secondary structure of a polypeptide.
35) The bonding of two amino acid molecules to form a larger molecule requires
A) the release of a water molecule.
44) Which bond is closest to the N-terminus of the molecule?
Answer: A
42) At which bond would water need to be added to achieve hydrolysis of the peptide, back to its component amino acid?
Answer: C
43) Which bond is a peptide bond?
Answer: C
45) Which bond is closest to the carboxyl end of the molecule?
Answer: E
73) A double-stranded DNA molecule contains a total of 120 purines and 120 pyrimidines. This DNA molecule could be composed of
B) 120 thymine and 120 adenine molecules.
91) Which of the following molecules act as building blocks (monomers) of polypeptides?
B) 2, 7, and 8
77) If one strand of a DNA molecule has the sequence of bases 5ʹATTGCA3ʹ, the other complementary strand would have the sequence
B) 3ʹTAACGT5ʹ.
85) Which molecule has hydrophilic and hydrophobic properties and would be found in plasma membranes?
B) 5
99) Which of the following molecules consists of a hydrophilic ʺheadʺ region and a hydrophobic ʺtailʺ region?
B) 5
56) The R group or side chain of the amino acid serine is —CH2OH. The R group or side chain of the amino acid alanine is —CH3. Where would you expect to find these amino acids in a globular protein in aqueous solution?
B) Alanine would be in the interior, and serine would be on the exterior of the globular protein.
11) The molecular formula for glucose is C6H12O6. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions?
B) C18H30O15
37) Which of the following statements is/are true regarding the chemical reaction illustrated in Figure 5.5?
B) It results in a peptide bond.
1) For this pair of items, choose the option that best describes their relationship. (A) The number of alpha glucose 1-4 linkages in cellulose (B) The number of alpha glucose 1-4 linkages in starch
B) Item (A) is less than item (B).
3) For this pair of items, choose the option that best describes their relationship. (A) The number of cis double bonds in saturated fatty acids (B) The number of cis double bonds in unsaturated fatty acids
B) Item (A) is less than item (B).
66) Which of the following statements about the 5ʹ end of a polynucleotide strand of DNA is correct?
B) The 5ʹ end has a phosphate group attached to the number 5 carbon of ribose.
65) DNAase is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNAase?
B) The phosphodiester bonds between deoxyribose sugars would be broken.
33) Why are human sex hormones considered to be lipids?
B) They are steroids, which are not soluble in water.
22) All of the following statements concerning saturated fats are true except
B) They have multiple double bonds in the carbon chains of their fatty acids.
25) What is a triacylglycerol?
B) a lipid made with three fatty acids and glycerol
39) Polysaccharides, lipids, and proteins are similar in that they
B) are synthesized from monomers by dehydration reactions.
62) Which of the following uses the amino acid sequences of polypeptides to predict a proteinʹs three -dimensional structure?
B) bioinformatics
64) What is the term used for a protein molecule that assists in the proper folding of other proteins?
B) chaperonin
34) All of the following contain amino acids except
B) cholesterol.
78) What is the structural feature that allows DNA to replicate?
B) complementary pairing of the nitrogenous bases
70) Which of the following are nitrogenous bases of the pyrimidine type?
B) cytosine and uracil
23) A molecule with the formula C18H36O2 is probably a
B) fatty acid.
67) Of the following functions, the major purpose of RNA is to
B) function in the synthesis of protein.
71) Which of the following are nitrogenous bases of the purine type?
B) guanine and adenine
48) What maintains the secondary structure of a protein?
B) hydrogen bonds
79) A new organism is discovered in the forests of Costa Rica. Scientists there determine that the polypeptide sequence of hemoglobin from the new organism has 72 amino acid differences from humans, 65 differences from a gibbon, 49 differences from a rat, and 5 differences from a frog. These data suggest that the new organism
B) is more closely related to frogs than to humans.
82) Which of the following is a diverse group of hydrophobic molecules?
B) lipids
50) The α helix and the β pleated sheet are both common polypeptide forms found in which level of protein structure?
B) secondary
94) A fat (or triacylglycerol) would be formed as a result of a dehydration reaction between
B) three molecules of 9 and one molecule of 10.
8) How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long?
C) 10
88) Which molecule is glycerol?
C) 10
72) If a DNA sample were composed of 10% thymine, what would be the percentage of guanine?
C) 40
92) Which of the following molecules is an amino acid with a hydrophobic R group or side chain?
C) 7
93) Which of the following molecules could be joined together by a peptide bond as a result of a dehydration reaction?
C) 7and8
41) Upon chemical analysis, a particular polypeptide was found to contain 100 amino acids. How many peptide bonds are present in this protein?
C) 99
75) Which of the following statements best summarizes the structural differences between DNA and RNA?
C) DNA nucleotides contain a different sugar than RNA nucleotides.
2) For this pair of items, choose the option that best describes their relationship. (A) The probability of finding chitin in fungal cell walls (B) The probability of finding chitin in arthropod exoskeletons
C) Item (A) is exactly or very approximately equal to item (B).
28) Which of the following statements is true regarding the molecule illustrated in Figure 5.3?
C) Molecules of this type are usually liquid at room temperature
26) Which of the following is true regarding saturated fatty acids?
C) They are the principal molecules in lard and butter.
69) Which of the following descriptions best fits the class of molecules known as nucleotides?
C) a nitrogenous base, a phosphate group, and a pentose sugar
60) What method did Frederick Sanger use to elucidate the structure of insulin?
C) analysis of amino acid sequence of small fragments
7) What is the chemical mechanism by which cells make polymers from monomers?
C) dehydration reactions
36) There are 20 different amino acids. What makes one amino acid different from another?
C) different side chains (R groups) attached to an alpha (α) carbon
21) Humans can digest starch but not cellulose because
C) humans have enzymes that can hydrolyze the alpha (α) glycosidic linkages of starch but not the beta (β) glycosidic linkages of cellulose.
84) Enzymes are
C) proteins.
32) What is the structure shown in Figure 5.4?
C) steroid molecule
55) At which level of protein structure are interactions between the side chains (R groups) most important?
C) tertiary
53) The tertiary structure of a protein is the
C) unique three-dimensional shape of the fully folded polypeptide.
95) Which of the following molecules could be joined together by a phosphodiester type of covalent bond?
D) 11 and 12
86) Which of the following combinations could be linked together to form a nucleotide?
D) 11, 12, and 13
96) Which of the following molecules is the pentose sugar found in RNA?
D) 12
27) Which of the following statements is true regarding the molecule illustrated in Figure 5.2?
D) A and B only
57) Misfolding of polypeptides is a serious problem in cells. Which of the following diseases are associated with an accumulation of misfolded proteins?
D) A and B only
20) Which of the following is true of cellulose?
D) It is a major structural component of plant cell walls.
17) Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?
D) as a disaccharide
10) Which of the following polymers contain nitrogen?
D) chitin
54) A strong covalent bond between amino acids that functions in maintaining a polypeptideʹs specific three-dimensional shape is a (an)
D) disulfide bond.
49) Which type of interaction stabilizes the alpha (α) helix and the beta (β) pleated sheet structures of proteins?
D) hydrogen bonds
83) Which of the following store and transmit hereditary information?
D) nucleic acids
80) Which of the following is an example of hydrolysis?
D) the reaction of a fat, forming glycerol and fatty acids with the utilization of water
51) The structure depicted in Figure 5.7 shows the
D) α helix secondary structure of a polypeptide.
87) Which of the following molecules contain(s) an aldehyde type of carbonyl functional group?
E) 1 and 4
90) Which of the following molecules is a purine type of nitrogenous base?
E) 13
100) Which of the following statements is false?
E) 14 and 15 could be joined together to form a polypeptide.
97) Which of the following molecules contains a glycosidic linkage type of covalent bond?
E) 15
46) How many different kinds of polypeptides, each composed of 12 amino acids, could be synthesized using the 20 common amino acids?
E) 2012
89) Which molecule is a saturated fatty acid?
E) 9
9) Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?
E) A and B are correct.
16) Which of the following descriptors is true of the molecule shown in Figure 5.1?
E) A and C only
31) The hydrogenation of vegetable oil results in which of the following?
E) A, B, and C
40) Dehydration reactions are used in forming which of the following compounds?
E) A, B, and C
58) What would be an unexpected consequence of changing one amino acid in a protein consisting of 325 amino acids?
E) A, B, and C are correct.
14) A molecule with the chemical formula C6H12O6 is probably a
E) A, B, and C.
59) Altering which of the following levels of structural organization could change the function of a protein?
E) all of the above
74) The difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA
E) contains one less oxygen atom.
63) The function of each protein is a consequence of its specific shape. What is the term used for a change in a proteinʹs three-dimensional shape or conformation due to disruption of hydrogen bonds, disulfide bridges, or ionic bonds?
E) denaturation
76) In the double helix structure of nucleic acids, cytosine hydrogen bonds to
E) guanine.
81) The element nitrogen is present in all of the following except
E) monosaccharides.
29) The molecule shown in Figure 5.3 is a
E) unsaturated fatty acid.
