Question 1

Which of the following LEAST supports the idea of genome reduction?

Accepted Answer

A)  Pseudogenes found in some organisms are no longer expressed but have homology to functional genes in other species. 
B)  Virulence factors are found on pathogenicity islands. 
C)  Pathogenic shigellae lack major regions of genes that the closely related E. coli possesses. 
D)  Bacteria no longer need "pseudogenes" when growing in new environments. 
E)  Over half of the genome of the obligate intracellular pathogen, Mycobacterium leprae, is composed of pseudogenes that are no longer needed. 
A)  Pseudogenes found in some organisms are no longer expressed but have homology to functional genes in other species. 
B)  Virulence factors are found on pathogenicity islands. 
C)  Pathogenic shigellae lack major regions of genes that the closely related E. coli possesses. 
D)  Bacteria no longer need "pseudogenes" when growing in new environments. 
E)  Over half of the genome of the obligate intracellular pathogen, Mycobacterium leprae, is composed of pseudogenes that are no longer needed.

Question 2

CRISPR is considered an example of adaptive immunity in bacteria and archaea because it

Accepted Answer

A)  methylates host DNA and destroys invading DNA. 
B)  requires host "pac" sites in order to destroy invading DNA. 
C)  minimizes damage from foreign DNA by using guide RNA similar to the invader and cas proteins to cleave the foreign DNA. 
D)  prevents the production of cell surface receptors that allow phages to get into the cell. 
E)  prevents archaeal DNA from infecting bacteria. 
A)  methylates host DNA and destroys invading DNA. 
B)  requires host "pac" sites in order to destroy invading DNA. 
C)  minimizes damage from foreign DNA by using guide RNA similar to the invader and cas proteins to cleave the foreign DNA. 
D)  prevents the production of cell surface receptors that allow phages to get into the cell. 
E)  prevents archaeal DNA from infecting bacteria.

Question 3

Evolution toward pathogenicity may involve

Accepted Answer

A)  horizontal gene transfer. 
B)  gene loss. 
C)  gene acquisition. 
D)  horizontal gene transfer and gene acquisition. 
E)  horizontal gene transfer, gene loss, and gene acquisition. 
A)  horizontal gene transfer. 
B)  gene loss. 
C)  gene acquisition. 
D)  horizontal gene transfer and gene acquisition. 
E)  horizontal gene transfer, gene loss, and gene acquisition.

Question 4

Which of the following is NOT a feature of a transposon?

Accepted Answer

A)  ability to move around a genome 
B)  presence of inverted repeats at each end 
C)  the ability to transfer via a phage head 
D)  genes coding for a transposase activity 
E)  presence of antibiotic resistance genes 
A)  ability to move around a genome 
B)  presence of inverted repeats at each end 
C)  the ability to transfer via a phage head 
D)  genes coding for a transposase activity 
E)  presence of antibiotic resistance genes

Question 5

The following statements about superfamily proteins are true EXCEPT that

Accepted Answer

A)  ABC (ATP-binding cassette) transporters serve as an example. 
B)  proteins with structural and functional similarity but low sequence homology may be considered superfamilies. 
C)  superfamily proteins are encoded by genes found on superfamily islands. 
D)  superfamily proteins are encoded by genes that have been duplicates and then mutated. 
E)  proteins such as HSP70 that are found in all domains of life are examples. 
A)  ABC (ATP-binding cassette) transporters serve as an example. 
B)  proteins with structural and functional similarity but low sequence homology may be considered superfamilies. 
C)  superfamily proteins are encoded by genes found on superfamily islands. 
D)  superfamily proteins are encoded by genes that have been duplicates and then mutated. 
E)  proteins such as HSP70 that are found in all domains of life are examples.

Question 6

A derivative F plasmid that contains host DNA is called an ________ plasmid.

Accepted Answer

A)  F 
B)  F+ 
C)  F- 
D)  F' 
E)  Hfr 
A)  F 
B)  F+ 
C)  F- 
D)  F' 
E)  Hfr

Question 7

Why is SOS repair considered to be an error-prone repair mechanism? Why would an organism use an error-prone mechanism?

Accepted Answer

SOS repair occurs after extensive DNA da

Question 8

During generalized recombination, ________ proteins catalyze branch migration at crossovers called ________.

Accepted Answer

A)  RuvAB; Holliday junctions 
B)  RuvAB; duplexes 
C)  RecBCD; Holliday junctions 
D)  RecBCD; duplexes 
E)  RecA; duplexes 
A)  RuvAB; Holliday junctions 
B)  RuvAB; duplexes 
C)  RecBCD; Holliday junctions 
D)  RecBCD; duplexes 
E)  RecA; duplexes

Question 9

The main components of CRISPR anatomy include

Accepted Answer

A)  methylation sites on palindromic sequences. 
B)  int genes with att sites for homology. 
C)  inverted repeats and genes encoding transposase. 
D)  short direct repeats, spacers, and genes encoding cas proteins. 
E)  cell surface receptors. 
A)  methylation sites on palindromic sequences. 
B)  int genes with att sites for homology. 
C)  inverted repeats and genes encoding transposase. 
D)  short direct repeats, spacers, and genes encoding cas proteins. 
E)  cell surface receptors.

Question 10

The process in which bacteriophages carry host DNA from one cell to another is known as

Accepted Answer

A)  conjugation. 
B)  transformation. 
C)  transposition. 
D)  recombination. 
E)  transduction. 
A)  conjugation. 
B)  transformation. 
C)  transposition. 
D)  recombination. 
E)  transduction.

Question 11

Distinguish between generalized and specialized transduction.

Accepted Answer

Both types of transduction use bacteriop

Question 12

The difference between generalized and specialized transduction is

Accepted Answer

A)  the size of the plasmids being moved. 
B)  the size of the phages being used. 
C)  that in generalized transduction, chromosomes are moved, whereas in specialized transduction, plasmids are moved. 
D)  that in generalized transduction, any DNA can be moved, but with specialized transduction, only certain DNA near the phage site can be moved. 
E)  There is no difference. 
A)  the size of the plasmids being moved. 
B)  the size of the phages being used. 
C)  that in generalized transduction, chromosomes are moved, whereas in specialized transduction, plasmids are moved. 
D)  that in generalized transduction, any DNA can be moved, but with specialized transduction, only certain DNA near the phage site can be moved. 
E)  There is no difference.

Question 13

Which of the following statements is LEAST supportive of the idea that genetic exchange between bacteria occurs in the human gastrointestinal tract?

Accepted Answer

A)  the high bacterial cell density in this environment 
B)  the presence of mixed species and biofilms in this environment 
C)  the presence of dead bacteria as a source of extracellular DNA for transformation 
D)  the passage of antibiotic resistance genes from one bacterium to another within a patient 
E)  the presence of pseudogenes in bacteria 
A)  the high bacterial cell density in this environment 
B)  the presence of mixed species and biofilms in this environment 
C)  the presence of dead bacteria as a source of extracellular DNA for transformation 
D)  the passage of antibiotic resistance genes from one bacterium to another within a patient 
E)  the presence of pseudogenes in bacteria

Question 14

Which of the following forms of transposition specifically describes the transfer of DNA from one cell to another?

Accepted Answer

A)  nonreplicative 
B)  replicative 
C)  composite 
D)  complex 
E)  conjugative 
A)  nonreplicative 
B)  replicative 
C)  composite 
D)  complex 
E)  conjugative

Question 15

Describe two processes that may happen during the evolution toward pathogenicity.

Accepted Answer

First, bacteria may gain pathogenicity i

Question 16

CRISPR is viewed as the adaptive immune system of bacteria, yet restriction/modification systems also play roles in bacterial defense. Compare and contrast how both systems protect the host.

Accepted Answer

Restriction/modification systems are use

Question 17

When a population is under threat, which of the following would spread?

Accepted Answer

A)  F plasmids 
B)  bacteriophage 
C)  resistance plasmids 
D)  conjugative transposons 
E)  genome reductions 
A)  F plasmids 
B)  bacteriophage 
C)  resistance plasmids 
D)  conjugative transposons 
E)  genome reductions

Question 18

Which of the following is NOT true of a pyrimidine dimer?

Accepted Answer

A)  It can be repaired by photoreactivation. 
B)  The pyrimidines are base-paired one to another. 
C)  It is produced by ultraviolet light. 
D)  It blocks DNA replication. 
E)  It blocks transcription. 
A)  It can be repaired by photoreactivation. 
B)  The pyrimidines are base-paired one to another. 
C)  It is produced by ultraviolet light. 
D)  It blocks DNA replication. 
E)  It blocks transcription.

Question 19

An example of vertical gene transfer is the

Accepted Answer

A)  development of many genetically diverse mesorhizobia via incorporation of a 500 kB segment from a mesorhizobium. 
B)  uptake of beta-lactamase genes by Streptococcus pneumoniae. 
C)  transfer of CRISPR spacers to daughter cells during cell division. 
D)  transfer of a Ti plasmid from agrobacterium to a plant. 
E)  transfer of conjugative plasmids from one strain to another. 
A)  development of many genetically diverse mesorhizobia via incorporation of a 500 kB segment from a mesorhizobium. 
B)  uptake of beta-lactamase genes by Streptococcus pneumoniae. 
C)  transfer of CRISPR spacers to daughter cells during cell division. 
D)  transfer of a Ti plasmid from agrobacterium to a plant. 
E)  transfer of conjugative plasmids from one strain to another.

Question 20

Large regions of sequence homology are required when recombining DNA molecules by ________ recombination.

Accepted Answer

A)  general 
B)  site-specific 
C)  specialized 
D)  transposition 
E)  reversion 
A)  general 
B)  site-specific 
C)  specialized 
D)  transposition 
E)  reversion

Exam 9: Gene Transfer, Mutations, and Genome Evolution

Which of the following LEAST supports the idea of genome reduction?

CRISPR is considered an example of adaptive immunity in bacteria and archaea because it

Evolution toward pathogenicity may involve

Which of the following is NOT a feature of a transposon?

The following statements about superfamily proteins are true EXCEPT that

A derivative F plasmid that contains host DNA is called an ________ plasmid.

Why is SOS repair considered to be an error-prone repair mechanism? Why would an organism use an error-prone mechanism?

During generalized recombination, ________ proteins catalyze branch migration at crossovers called ________.

The main components of CRISPR anatomy include

The process in which bacteriophages carry host DNA from one cell to another is known as

Distinguish between generalized and specialized transduction.

The difference between generalized and specialized transduction is

Which of the following statements is LEAST supportive of the idea that genetic exchange between bacteria occurs in the human gastrointestinal tract?

Which of the following forms of transposition specifically describes the transfer of DNA from one cell to another?

Describe two processes that may happen during the evolution toward pathogenicity.

CRISPR is viewed as the adaptive immune system of bacteria, yet restriction/modification systems also play roles in bacterial defense. Compare and contrast how both systems protect the host.

When a population is under threat, which of the following would spread?

Which of the following is NOT true of a pyrimidine dimer?

An example of vertical gene transfer is the

Large regions of sequence homology are required when recombining DNA molecules by ________ recombination.

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Viruses

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

Filters

During generalized recombination, proteins catalyze branch migration at crossovers called .