Question 1

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 2

Phages that carry host DNA are called transducing particles. Describe how the Salmonella P22 phage accidentally packages host DNA.

Accepted Answer

The Salmonella P22 phage replicates via

Question 3

Approximately what percentage of the 4,288 open reading frames of E. coli have no known or annotated function?

Accepted Answer

A)  10 
B)  14 
C)  24 
D)  52 
E)  70 
A)  10 
B)  14 
C)  24 
D)  52 
E)  70

Question 4

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 5

Mutations that occur even in the absence of an added mutagen are known as ________ mutations.

Accepted Answer

A)  spontaneous 
B)  silent 
C)  missense 
D)  nonsense 
E)  frameshift 
A)  spontaneous 
B)  silent 
C)  missense 
D)  nonsense 
E)  frameshift

Question 6

Ames used his reversion test with Salmonella to screen compounds for

Accepted Answer

A)  virulence. 
B)  pathogenicity. 
C)  toxicity. 
D)  antibiotics. 
E)  mutagenicity. 
A)  virulence. 
B)  pathogenicity. 
C)  toxicity. 
D)  antibiotics. 
E)  mutagenicity.

Question 7

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 8

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 9

Consider a culture of 1,000 cells. Each cell divides once to yield a total of 2,000 cells. A measurement of the mutation rate in this culture would be based on the total number of

Accepted Answer

A)  2,000 cells. 
B)  genes in the bacterium. 
C)  generations, which in this case is one. 
D)  cell divisions, which is 1,000. 
E)  mutations found in that culture. 
A)  2,000 cells. 
B)  genes in the bacterium. 
C)  generations, which in this case is one. 
D)  cell divisions, which is 1,000. 
E)  mutations found in that culture.

Question 10

Which of the following is evidence of gene reduction?

Accepted Answer

A)  altered GC content 
B)  different codon usage 
C)  pseudogenes 
D)  genomic islands 
E)  transposons 
A)  altered GC content 
B)  different codon usage 
C)  pseudogenes 
D)  genomic islands 
E)  transposons

Question 11

Competence in Gram-positive organisms is induced by

Accepted Answer

A)  calcium and cold. 
B)  electrical currents. 
C)  competence factors made of peptides. 
D)  presence of biofilm. 
E)  Competence is not induced in Gram-positive bacteria. 
A)  calcium and cold. 
B)  electrical currents. 
C)  competence factors made of peptides. 
D)  presence of biofilm. 
E)  Competence is not induced in Gram-positive bacteria.

Question 12

Which of the following bacteria requires artificial assistance to become competent to take up DNA?

Accepted Answer

A)  Bacillus 
B)  E. coli 
C)  Haemophilus 
D)  Neisseria 
E)  Streptococcus 
A)  Bacillus 
B)  E. coli 
C)  Haemophilus 
D)  Neisseria 
E)  Streptococcus

Question 13

Compare and contrast general and site-specific recombination.

Accepted Answer

New pieces of DNA entering a cell, or DN

Question 14

Describe the process whereby DNA is transferred from Agrobacterium to plants.

Accepted Answer

First, phenolic compounds are released f

Question 15

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 16

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 17

Describe four of the error-proof DNA repair mechanisms.

Accepted Answer

Any four of the following are acceptable

Question 18

Distinguish between generalized and specialized transduction.

Accepted Answer

Both types of transduction use bacteriop

Question 19

Outline any three characteristics of the human gastrointestinal tract that makes it an ideal environment for genetic exchange.

Accepted Answer

Any of the following are acceptable:
The

Question 20

Which of the following is NOT an example of a genomic island?

Accepted Answer

A)  pathogenicity islands in infectious organisms 
B)  symbiosis islands in Mesorhizobium 
C)  resistance islands in Staphylococcus 
D)  transposition islands within bacteria 
E)  metabolic islands within Salmonella 
A)  pathogenicity islands in infectious organisms 
B)  symbiosis islands in Mesorhizobium 
C)  resistance islands in Staphylococcus 
D)  transposition islands within bacteria 
E)  metabolic islands within Salmonella

Exam 9: Gene Transfer, Mutations, and Genome Evolution

Evolution toward pathogenicity may involve

Phages that carry host DNA are called transducing particles. Describe how the Salmonella P22 phage accidentally packages host DNA.

Approximately what percentage of the 4,288 open reading frames of E. coli have no known or annotated function?

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

Mutations that occur even in the absence of an added mutagen are known as ________ mutations.

Ames used his reversion test with Salmonella to screen compounds for

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

The main components of CRISPR anatomy include

Consider a culture of 1,000 cells. Each cell divides once to yield a total of 2,000 cells. A measurement of the mutation rate in this culture would be based on the total number of

Which of the following is evidence of gene reduction?

Competence in Gram-positive organisms is induced by

Which of the following bacteria requires artificial assistance to become competent to take up DNA?

Compare and contrast general and site-specific recombination.

Describe the process whereby DNA is transferred from Agrobacterium to plants.

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

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

Describe four of the error-proof DNA repair mechanisms.

Distinguish between generalized and specialized transduction.

Outline any three characteristics of the human gastrointestinal tract that makes it an ideal environment for genetic exchange.

Which of the following is NOT an example of a genomic island?

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

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