,ch 1 - 5
Indicate the answer choice that best completes the statement or answers the question.
1. Which statement about DNA structure is INCORRECT?
a. It is a branched polymer with a flexible backbone.
b. The DNA backbone is built of repeating sugar–phosphate units.
c. Each DNA strand has directionality due to identical orientation of the sugar–phosphate units.
d. Each sugar is connected to two phosphate groups through different linkages.
e. Its structure is a double helix composed of two intertwined strands.
2. What method can be used to separate proteins only by their charge?
a. gel-filtration chromatography
b. affinity chromatography
c. gel electrophoresis
d. ion-exchange chromatography
e. dialysis
3. pUC plasmids are useful for screening cells that contain recombinant DNA because they contain the
gene.
a. β-galactosidase
b. tetracycline resistance
c. green fluorescent protein
d. luciferase
e. DNA polymerase
4. Why are free interactions of water molecules in bulk water more favorable than more ordered interactions
with nonpolar compounds?
a. The total entropy in such interactions increases because the Gibbs free energy is positive.
b. The total entropy in such interactions decreases because the Gibbs free energy is negative.
c. The enthalpy of the ordered state is lower than the enthalpy of the bulk state.
d. The total entropy in such interactions increases because the Gibbs free energy is negative.
e. The total entropy in such interactions decreases because the Gibbs free energy is positive.
5. The lacZα gene encodes the fragment of the:
a. α-galactosidase.
b. carbohydrase.
c. β-galactosidase.
d. α-amylase.
e. β-amylase.
6. What isomers of amino acids are found in proteins and what absolute configuration do they have?
,ch 1a.- 5L isomer; R absolute configuration
b. D and L isomers; R absolute configuration
c. L isomer; S absolute configuration
d. D isomer; S absolute configuration
e. L and D isomers; S absolute configuration
7. What process generates different mRNA that are templates for different forms of a protein without requiring
a gene for each protein?
a. transcription
b. exon shuffling
c. degenerate splicing
d. alternative splicing
e. recombination
8. What technique can be used to determine the mass-to-charge ratio of a molecule?
a. Edman degradation
b. affinity chromatography
c. diagonal electrophoresis
d. MALDI-TOF
e. SDS-PAGE
9. Each three-base codon encodes a specific:
a. DNA nucleotide.
b. mRNA nucleotide.
c. tRNA nucleotide.
d. rRNA nucleotide.
e. amino acid.
10. What DNA sequence contains a palindromic inverted repeat such as those recognized by restriction
enzymes? (Note: Only one strand is shown.)
a. CAGTCC
b. GCATCC
c. CGATTAGC
d. GAGAGAGA
e. GCATATGC
11. A protein with a molecular weight of 75 550 g mol–1 has a mass of:
a. 75,550 Da or 755.5 kDa.
b. 7555 Da or 75.55 kDa.
, ch 1 - 5
c. 75,550 Da or 75.55 kDa.
d. 755,500 Da or 7.555 kDa.
e. 7,555,000 Da or 75550 kDa.
12. What releases a peptide from beads after solid-phase synthesis?
a. trifluoroacetic acid
b. dicyclohexylcarbodiimide
c. hydrofluoric acid
d. fluoroacetic acid
e. water
13. Which amino acid has the one-letter abbreviation K?
a. histidine
b. asparagine
c. alanine
d. valine
e. lysine
14. The amino termini acetylation of proteins:
a. makes these proteins negatively charged.
b. makes these proteins more resistant to degradation.
c. induces their conformation change.
d. makes these proteins hydrophobic.
e. makes these proteins less exposed to mutations.
15. Which statement about biological diversity is FALSE?
a. The plant kingdom includes species as relatively simple as algae and as complex as sequoias.
b. No species can live in seemingly hostile environments such as hot springs and glaciers.
c. Animal kingdom species range from nearly microscopic to very large.
d. Organisms such as protozoa, yeast, and bacteria are present with great diversity in water and soil.
e. Microscopic organisms can live on or within larger organisms.
16. What does an α-amino acid consist of?
a. carbonyl group, α carbon, amino group, oxygen atom, distinctive R group
b. carboxylic acid group, α carbon, amino group, hydrogen atom, distinctive R group
c. carboxylic acid group, ε carbon, nitro group, hydrogen atom
d. alcohol group, α carbon, amino group, nitrogen atom, distinctive R group, hydrogen atom
e. carboxylic acid group, δ carbon, imine radical, hydrogen atom, distinctive R group
17. Order the type of interactions by the bond strength in descending value.
Indicate the answer choice that best completes the statement or answers the question.
1. Which statement about DNA structure is INCORRECT?
a. It is a branched polymer with a flexible backbone.
b. The DNA backbone is built of repeating sugar–phosphate units.
c. Each DNA strand has directionality due to identical orientation of the sugar–phosphate units.
d. Each sugar is connected to two phosphate groups through different linkages.
e. Its structure is a double helix composed of two intertwined strands.
2. What method can be used to separate proteins only by their charge?
a. gel-filtration chromatography
b. affinity chromatography
c. gel electrophoresis
d. ion-exchange chromatography
e. dialysis
3. pUC plasmids are useful for screening cells that contain recombinant DNA because they contain the
gene.
a. β-galactosidase
b. tetracycline resistance
c. green fluorescent protein
d. luciferase
e. DNA polymerase
4. Why are free interactions of water molecules in bulk water more favorable than more ordered interactions
with nonpolar compounds?
a. The total entropy in such interactions increases because the Gibbs free energy is positive.
b. The total entropy in such interactions decreases because the Gibbs free energy is negative.
c. The enthalpy of the ordered state is lower than the enthalpy of the bulk state.
d. The total entropy in such interactions increases because the Gibbs free energy is negative.
e. The total entropy in such interactions decreases because the Gibbs free energy is positive.
5. The lacZα gene encodes the fragment of the:
a. α-galactosidase.
b. carbohydrase.
c. β-galactosidase.
d. α-amylase.
e. β-amylase.
6. What isomers of amino acids are found in proteins and what absolute configuration do they have?
,ch 1a.- 5L isomer; R absolute configuration
b. D and L isomers; R absolute configuration
c. L isomer; S absolute configuration
d. D isomer; S absolute configuration
e. L and D isomers; S absolute configuration
7. What process generates different mRNA that are templates for different forms of a protein without requiring
a gene for each protein?
a. transcription
b. exon shuffling
c. degenerate splicing
d. alternative splicing
e. recombination
8. What technique can be used to determine the mass-to-charge ratio of a molecule?
a. Edman degradation
b. affinity chromatography
c. diagonal electrophoresis
d. MALDI-TOF
e. SDS-PAGE
9. Each three-base codon encodes a specific:
a. DNA nucleotide.
b. mRNA nucleotide.
c. tRNA nucleotide.
d. rRNA nucleotide.
e. amino acid.
10. What DNA sequence contains a palindromic inverted repeat such as those recognized by restriction
enzymes? (Note: Only one strand is shown.)
a. CAGTCC
b. GCATCC
c. CGATTAGC
d. GAGAGAGA
e. GCATATGC
11. A protein with a molecular weight of 75 550 g mol–1 has a mass of:
a. 75,550 Da or 755.5 kDa.
b. 7555 Da or 75.55 kDa.
, ch 1 - 5
c. 75,550 Da or 75.55 kDa.
d. 755,500 Da or 7.555 kDa.
e. 7,555,000 Da or 75550 kDa.
12. What releases a peptide from beads after solid-phase synthesis?
a. trifluoroacetic acid
b. dicyclohexylcarbodiimide
c. hydrofluoric acid
d. fluoroacetic acid
e. water
13. Which amino acid has the one-letter abbreviation K?
a. histidine
b. asparagine
c. alanine
d. valine
e. lysine
14. The amino termini acetylation of proteins:
a. makes these proteins negatively charged.
b. makes these proteins more resistant to degradation.
c. induces their conformation change.
d. makes these proteins hydrophobic.
e. makes these proteins less exposed to mutations.
15. Which statement about biological diversity is FALSE?
a. The plant kingdom includes species as relatively simple as algae and as complex as sequoias.
b. No species can live in seemingly hostile environments such as hot springs and glaciers.
c. Animal kingdom species range from nearly microscopic to very large.
d. Organisms such as protozoa, yeast, and bacteria are present with great diversity in water and soil.
e. Microscopic organisms can live on or within larger organisms.
16. What does an α-amino acid consist of?
a. carbonyl group, α carbon, amino group, oxygen atom, distinctive R group
b. carboxylic acid group, α carbon, amino group, hydrogen atom, distinctive R group
c. carboxylic acid group, ε carbon, nitro group, hydrogen atom
d. alcohol group, α carbon, amino group, nitrogen atom, distinctive R group, hydrogen atom
e. carboxylic acid group, δ carbon, imine radical, hydrogen atom, distinctive R group
17. Order the type of interactions by the bond strength in descending value.
