Test Bank for Biochemistry 7e Jeremy Berg John Tymoczko Lubert Stryer (All Chapters Test Bank, 100%
Original Verified, A+ Grade)
1. The genetic information present in DNA is described by
a. the base composition of the DNA.
b. the double-helical backbone structure of the DNA.
*c. the sequence of bases along a DNA strand.
3. Which of the following observations or predictions is accepted about the human
genome?
a. It contains about 100,000 genes.
b. Only one protein can be made per gene.
*c. About 3% of the human genome codes for protein.
4. Water is said to be highly cohesive because water molecules interact with one another
through
a. van der Waals interactions.
*b. hydrogen bonds.
c. covalent bonding.
5. A biological molecule can serve as a hydrogen bond donor if the hydrogen is attached
to
*a. oxygen or nitrogen.
b. any nonmetallic atom.
c. carbon.
6. Carl Woese and coworkers discovered that prokaryotes could be divided in to two
domains: Bacteria and Archaea. Based on a recent evolutionary tree, how are Eukaryotes
related to these domains?
*a. Eukaryotes are more closely related to Archaea than to Bacteria.
b. Eukaryotes are more closely related to Bacteria than to Archaea.
c. Eukaryotes form a distinct lineage with no relationship to either Bacteria or
Archaea.
7. The Second Law of Thermodynamics states that:
a. The entropy of a system increases if a process is spontaneous.
b. The entropy of a system's surroundings increases if a process is spontaneous.
, *c. The total entropy of a system plus its surroundings increases if a process is
spontaneous.
8. What must be true of the free energy change, ΔG, for a reaction to be spontaneous?
*a. It must be negative.
b. It must be greater than the change in entropy.
c. It is dominated by the enthalpy change, ΔH.
9. Which is an appropriate statement of involvement of the hydrophobic effect in protein
folding?
a. Polar portions of the molecule are generally exposed to solvent to interact
effectively with water.
b. Nonpolar portions of the molecule can be placed on the surface of the
molecule only if hydrogen bonded to water.
*c. Nonpolar portions of the molecule associate with one another on the interior
of the protein.
10. The dielectric constant of the interior of a protein is considerably smaller than that of
water. How would you expect this to affect the strength of an electrostatic interaction
between two opposite charges with the same distance between them if the charged groups
were located in the interior of the protein rather than on its surface?
a. The strength of interaction would be stronger if the interacting charges were
on the surface of the protein.
*b. The strength of interaction would be stronger if the interacting charges were
on the interior of the protein.
c. The strength of interaction of the interacting charges should be independent of
their location in the protein.
11. Which of the following is true regarding the chirality of amino acids found in
proteins?
*a. Only L amino acids are found in proteins.
b. Only D amino acids are found in proteins.
c. Proteins contain both D and L amino acids.
12. Of the 20 amino acids from which proteins are made, which is most likely to be
present with its R-group in a mixture of ionization states near physiological pH?
a. Tyr
, *b. His
c. Glu
13. The conversion of cysteine to cystine is what kind of reaction?
*a. an oxidation
b. a reduction
c. an addition
14. Which of the following is NOT true of peptide bonds?
a. They tend to be planar.
b. They are generally in the trans and rarely in the cis configuration.
*c. They tend to have the amide nitrogen protonated to give a positive charge.
15. What do α-helices and β-sheets have in common?
*a. Both are stabilized by hydrogen bonding involving carbonyl oxygens and
amide nitrogens.
b. The same amino acids stabilize both forms of secondary structure.
c. The length of a 10-amino acid α-helix and β-sheet strand will be the same.
16. Water-soluble proteins such as myoglobin tend to fold such that:
*a. hydrophobic amino acid R-groups are on the interior of the protein and
hydrophilic groups are on the outside.
b. hydrophilic amino acid R-groups are on the interior of the protein and
hydrophobic groups are on the outside.
c. all peptides form hydrogen bonds with water.
17. α-helices and β-sheets are often found to be amphipathic. This means that
a. They have positive charges on one side and negative charges on the other.
b. They have large R-groups on one side and small R-groups on the other as
small groups are easier to pack in the interior of the protein.
*c. They have one side or face that is predominately polar with the other side
being predominately hydrophobic.
18. The major conclusion of the experiment of C. Anfinsen involving ribonuclease was
that:
, *a. The information on how the protein should fold was contained in the amino
acid sequence.
b. A denatured protein loses its enzymatic activity.
c. The protein could be refolded correctly only if the disulfide bonds were left
intact.
19. Protein folding is often described as a highly cooperative process. This means that
a. The folding of a given protein requires cooperation of a number of other
proteins.
*b. The folding of a protein is largely an all-or-none process.
c. A protein only folds correctly when present in its normal cellular
environment.
20. For the peptide Ala-Arg-Lys-Ala-Asn-Ser-Ala-Ser, what would be the expected
charges at pH 1, 7, and 13?
a. +3, +3, 0
b. +2, +2, -1
*c. +3, +2, -1
21. If one wanted a very precise determination of the mass of a protein, what would be
the method of choice?
a. gel filtration chromatography
b. SDS polyacrylamide gel electrophoresis
*c. mass spectrometry
22. A protein has been eluted from a DEAE-cellulose column by washing with a salt-
containing solution. Before the protein is subjected to a quantification assay, you need to
remove the salt, as it can interfere with the activity to be measured. Which of the
following would NOT accomplish the removal of salt from your sample?
*a. passage through a carboxymethyl-cellulose column
b. passage through a gel filtration column
c. dialysis
23. SDS polyacrylamide electrophoresis could be used to do which of the following?
a. Determine the molecular weight of an oligomeric (multisubunit) protein.
*b. Determine the molecular weights of subunits of an oligomeric protein.
Original Verified, A+ Grade)
1. The genetic information present in DNA is described by
a. the base composition of the DNA.
b. the double-helical backbone structure of the DNA.
*c. the sequence of bases along a DNA strand.
3. Which of the following observations or predictions is accepted about the human
genome?
a. It contains about 100,000 genes.
b. Only one protein can be made per gene.
*c. About 3% of the human genome codes for protein.
4. Water is said to be highly cohesive because water molecules interact with one another
through
a. van der Waals interactions.
*b. hydrogen bonds.
c. covalent bonding.
5. A biological molecule can serve as a hydrogen bond donor if the hydrogen is attached
to
*a. oxygen or nitrogen.
b. any nonmetallic atom.
c. carbon.
6. Carl Woese and coworkers discovered that prokaryotes could be divided in to two
domains: Bacteria and Archaea. Based on a recent evolutionary tree, how are Eukaryotes
related to these domains?
*a. Eukaryotes are more closely related to Archaea than to Bacteria.
b. Eukaryotes are more closely related to Bacteria than to Archaea.
c. Eukaryotes form a distinct lineage with no relationship to either Bacteria or
Archaea.
7. The Second Law of Thermodynamics states that:
a. The entropy of a system increases if a process is spontaneous.
b. The entropy of a system's surroundings increases if a process is spontaneous.
, *c. The total entropy of a system plus its surroundings increases if a process is
spontaneous.
8. What must be true of the free energy change, ΔG, for a reaction to be spontaneous?
*a. It must be negative.
b. It must be greater than the change in entropy.
c. It is dominated by the enthalpy change, ΔH.
9. Which is an appropriate statement of involvement of the hydrophobic effect in protein
folding?
a. Polar portions of the molecule are generally exposed to solvent to interact
effectively with water.
b. Nonpolar portions of the molecule can be placed on the surface of the
molecule only if hydrogen bonded to water.
*c. Nonpolar portions of the molecule associate with one another on the interior
of the protein.
10. The dielectric constant of the interior of a protein is considerably smaller than that of
water. How would you expect this to affect the strength of an electrostatic interaction
between two opposite charges with the same distance between them if the charged groups
were located in the interior of the protein rather than on its surface?
a. The strength of interaction would be stronger if the interacting charges were
on the surface of the protein.
*b. The strength of interaction would be stronger if the interacting charges were
on the interior of the protein.
c. The strength of interaction of the interacting charges should be independent of
their location in the protein.
11. Which of the following is true regarding the chirality of amino acids found in
proteins?
*a. Only L amino acids are found in proteins.
b. Only D amino acids are found in proteins.
c. Proteins contain both D and L amino acids.
12. Of the 20 amino acids from which proteins are made, which is most likely to be
present with its R-group in a mixture of ionization states near physiological pH?
a. Tyr
, *b. His
c. Glu
13. The conversion of cysteine to cystine is what kind of reaction?
*a. an oxidation
b. a reduction
c. an addition
14. Which of the following is NOT true of peptide bonds?
a. They tend to be planar.
b. They are generally in the trans and rarely in the cis configuration.
*c. They tend to have the amide nitrogen protonated to give a positive charge.
15. What do α-helices and β-sheets have in common?
*a. Both are stabilized by hydrogen bonding involving carbonyl oxygens and
amide nitrogens.
b. The same amino acids stabilize both forms of secondary structure.
c. The length of a 10-amino acid α-helix and β-sheet strand will be the same.
16. Water-soluble proteins such as myoglobin tend to fold such that:
*a. hydrophobic amino acid R-groups are on the interior of the protein and
hydrophilic groups are on the outside.
b. hydrophilic amino acid R-groups are on the interior of the protein and
hydrophobic groups are on the outside.
c. all peptides form hydrogen bonds with water.
17. α-helices and β-sheets are often found to be amphipathic. This means that
a. They have positive charges on one side and negative charges on the other.
b. They have large R-groups on one side and small R-groups on the other as
small groups are easier to pack in the interior of the protein.
*c. They have one side or face that is predominately polar with the other side
being predominately hydrophobic.
18. The major conclusion of the experiment of C. Anfinsen involving ribonuclease was
that:
, *a. The information on how the protein should fold was contained in the amino
acid sequence.
b. A denatured protein loses its enzymatic activity.
c. The protein could be refolded correctly only if the disulfide bonds were left
intact.
19. Protein folding is often described as a highly cooperative process. This means that
a. The folding of a given protein requires cooperation of a number of other
proteins.
*b. The folding of a protein is largely an all-or-none process.
c. A protein only folds correctly when present in its normal cellular
environment.
20. For the peptide Ala-Arg-Lys-Ala-Asn-Ser-Ala-Ser, what would be the expected
charges at pH 1, 7, and 13?
a. +3, +3, 0
b. +2, +2, -1
*c. +3, +2, -1
21. If one wanted a very precise determination of the mass of a protein, what would be
the method of choice?
a. gel filtration chromatography
b. SDS polyacrylamide gel electrophoresis
*c. mass spectrometry
22. A protein has been eluted from a DEAE-cellulose column by washing with a salt-
containing solution. Before the protein is subjected to a quantification assay, you need to
remove the salt, as it can interfere with the activity to be measured. Which of the
following would NOT accomplish the removal of salt from your sample?
*a. passage through a carboxymethyl-cellulose column
b. passage through a gel filtration column
c. dialysis
23. SDS polyacrylamide electrophoresis could be used to do which of the following?
a. Determine the molecular weight of an oligomeric (multisubunit) protein.
*b. Determine the molecular weights of subunits of an oligomeric protein.
