Chapter 09: Bacterial Genomes and Evolution
MULTIPLE CHOICE
1. Griffith’s observations from his experiments infecting mice with smooth and rough strain
Streptococcus pneumoniae were later found to be due to
a. conjugation. c. transduction.
b. transposition. d. transformation.
ANS: D DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Understanding
2. Why might an organism transform DNA that is homologous to its own?
a. as a food source
b. to obtain new DNA
c. to repair its own damaged genome
d. Organisms are not capable of transforming homologous DNA.
ANS: C DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Understanding
3. What specifically is passed from the donor cell to the recipient cell during conjugation?
a. single-stranded DNA c. protein subunits
b. double-stranded DNA d. F factor pilus
ANS: A DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Understanding
4. Which of the following is NOT a step in the transduction process?
a. The DNA phage enters a bacterial cell by endocytosis.
b. The phage DNA commandeers host protein synthesis machinery.
c. The phage uses host cell DNA replication machinery.
d. Completed phage particles are released into the environment by lysing.
ANS: A DIF: Easy REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Remembering
5. Which of the following forms of horizontal gene transfer involves a prophage?
a. generalized transduction
b. specialized transduction
c. F factor conjugation
d. competence-mediated transformation
ANS: B DIF: Easy REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
, mediated transduction,and conjugation. MSC: Remembering
6. How do bacteria protect their own DNA from restriction enzymes?
a. restriction digestion c. generalized recombination
b. methylation of target sequences d. site-specific recombination
ANS: B DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Applying
7. A protein called integrase is encoded by ________ and allows for site-specific recombination in C.
diphtheria.
a. E. coli c. C. diphtheria
b. S. pneumoniae d. beta phage
ANS: D DIF: Moderate REF: 9.1
OBJ: 9.1b Describe how DNA molecules recombine by homologous recombination and site-specific
recombination. MSC: Understanding
8. The elements that form living organisms first originated from
a. viruses. c. water.
b. stardust. d. the oceans.
ANS: B DIF: Easy REF: 9.2
OBJ: 9.2a Describe how all life originated from microbes, how life-forms evolved over time, and
how species continue to evolve. MSC: Remembering
9. Which of the following does NOT lead to divergence?
a. fossilization c. transposition
b. mutations d. transduction
ANS: A DIF: Moderate REF: 9.2
OBJ: 9.2b Explain how microbial genomes change via processes of random mutation and natural
selection. MSC: Applying
10. Which of the following is NOT a good scenario for a molecular clock?
a. The gene used has the same function across all species being compared.
b. The generation time is the same for all species being compared.
c. The average mutation rate is constant among species.
d. The gene used is nonessential.
ANS: D DIF: Moderate REF: 9.2
OBJ: 9.2c Explain how a molecular clock works to measure phylogeny, and describe the key
attributes of a useful molecular clock gene. MSC: Understanding
11. If the mutation rate is not the same for all species being compared using a molecular clock, what does
a phylogenetic tree demonstrate?
a. the time since two species diverged from a common ancestor
b. the amount of evolutionary distance between two species
c. the generation time for species
d. the induced mutation frequency between two species
, ANS: B DIF: Difficult REF: 9.2
OBJ: 9.2c Explain how a molecular clock works to measure phylogeny, and describe the key
attributes of a useful molecular clock gene. MSC: Analyzing
12. Examine the figure shown. Which organism does NOT share the same common ancestor as
Escherichia and Erwinia carotovora?
a. Sodalis glossinidius c. Klebsiella
b. Photorhabdus luminescens d. Salmonella
ANS: A DIF: Moderate REF: 9.2
OBJ: 9.2c Explain how a molecular clock works to measure phylogeny, and describe the key
attributes of a useful molecular clock gene. MSC: Applying
13. Which of the following domains of life contain ether linkages in their membranes?
a. viral c. bacteria
b. eukarya d. archaea
ANS: D DIF: Moderate REF: 9.2
OBJ: 9.2d Describe the three domains of life. MSC: Understanding
14. Meaningful evolution occurs when
a. a changed trait affects survival.
b. a changed trait gives an organism an advantage.
c. a changed trait gives an organism a disadvantage.
d. environmental factors change.
ANS: A DIF: Moderate REF: 9.3
OBJ: 9.3a Explain how fitness of a trait depends on the environment and how environment-
dependent fitness leads to the evolution of antibiotic resistance in pathogens.
MSC: Understanding
15. Examine the figure shown. What happened to transform the original MRSA isolate into the small-
colony variant?
MULTIPLE CHOICE
1. Griffith’s observations from his experiments infecting mice with smooth and rough strain
Streptococcus pneumoniae were later found to be due to
a. conjugation. c. transduction.
b. transposition. d. transformation.
ANS: D DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Understanding
2. Why might an organism transform DNA that is homologous to its own?
a. as a food source
b. to obtain new DNA
c. to repair its own damaged genome
d. Organisms are not capable of transforming homologous DNA.
ANS: C DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Understanding
3. What specifically is passed from the donor cell to the recipient cell during conjugation?
a. single-stranded DNA c. protein subunits
b. double-stranded DNA d. F factor pilus
ANS: A DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Understanding
4. Which of the following is NOT a step in the transduction process?
a. The DNA phage enters a bacterial cell by endocytosis.
b. The phage DNA commandeers host protein synthesis machinery.
c. The phage uses host cell DNA replication machinery.
d. Completed phage particles are released into the environment by lysing.
ANS: A DIF: Easy REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Remembering
5. Which of the following forms of horizontal gene transfer involves a prophage?
a. generalized transduction
b. specialized transduction
c. F factor conjugation
d. competence-mediated transformation
ANS: B DIF: Easy REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
, mediated transduction,and conjugation. MSC: Remembering
6. How do bacteria protect their own DNA from restriction enzymes?
a. restriction digestion c. generalized recombination
b. methylation of target sequences d. site-specific recombination
ANS: B DIF: Moderate REF: 9.1
OBJ: 9.1a Explain how genetic information moves between bacteria by transformation, phage-
mediated transduction,and conjugation. MSC: Applying
7. A protein called integrase is encoded by ________ and allows for site-specific recombination in C.
diphtheria.
a. E. coli c. C. diphtheria
b. S. pneumoniae d. beta phage
ANS: D DIF: Moderate REF: 9.1
OBJ: 9.1b Describe how DNA molecules recombine by homologous recombination and site-specific
recombination. MSC: Understanding
8. The elements that form living organisms first originated from
a. viruses. c. water.
b. stardust. d. the oceans.
ANS: B DIF: Easy REF: 9.2
OBJ: 9.2a Describe how all life originated from microbes, how life-forms evolved over time, and
how species continue to evolve. MSC: Remembering
9. Which of the following does NOT lead to divergence?
a. fossilization c. transposition
b. mutations d. transduction
ANS: A DIF: Moderate REF: 9.2
OBJ: 9.2b Explain how microbial genomes change via processes of random mutation and natural
selection. MSC: Applying
10. Which of the following is NOT a good scenario for a molecular clock?
a. The gene used has the same function across all species being compared.
b. The generation time is the same for all species being compared.
c. The average mutation rate is constant among species.
d. The gene used is nonessential.
ANS: D DIF: Moderate REF: 9.2
OBJ: 9.2c Explain how a molecular clock works to measure phylogeny, and describe the key
attributes of a useful molecular clock gene. MSC: Understanding
11. If the mutation rate is not the same for all species being compared using a molecular clock, what does
a phylogenetic tree demonstrate?
a. the time since two species diverged from a common ancestor
b. the amount of evolutionary distance between two species
c. the generation time for species
d. the induced mutation frequency between two species
, ANS: B DIF: Difficult REF: 9.2
OBJ: 9.2c Explain how a molecular clock works to measure phylogeny, and describe the key
attributes of a useful molecular clock gene. MSC: Analyzing
12. Examine the figure shown. Which organism does NOT share the same common ancestor as
Escherichia and Erwinia carotovora?
a. Sodalis glossinidius c. Klebsiella
b. Photorhabdus luminescens d. Salmonella
ANS: A DIF: Moderate REF: 9.2
OBJ: 9.2c Explain how a molecular clock works to measure phylogeny, and describe the key
attributes of a useful molecular clock gene. MSC: Applying
13. Which of the following domains of life contain ether linkages in their membranes?
a. viral c. bacteria
b. eukarya d. archaea
ANS: D DIF: Moderate REF: 9.2
OBJ: 9.2d Describe the three domains of life. MSC: Understanding
14. Meaningful evolution occurs when
a. a changed trait affects survival.
b. a changed trait gives an organism an advantage.
c. a changed trait gives an organism a disadvantage.
d. environmental factors change.
ANS: A DIF: Moderate REF: 9.3
OBJ: 9.3a Explain how fitness of a trait depends on the environment and how environment-
dependent fitness leads to the evolution of antibiotic resistance in pathogens.
MSC: Understanding
15. Examine the figure shown. What happened to transform the original MRSA isolate into the small-
colony variant?
