Question 1

Which of the following is the most frequently used method of horizontal gene transfer used by bacteria?

Accepted Answer

A)  Transformation 
B)  Transduction 
C)  Conjugation 
D)  Transposons 
A)  Transformation 
B)  Transduction 
C)  Conjugation 
D)  Transposons

Question 2

What structure is labeled y in the illustration?

Accepted Answer

A)  DNA polymerase I 
B)  DNA ligase 
C)  Photolyase 
D)  Endonuclease 
A)  DNA polymerase I 
B)  DNA ligase 
C)  Photolyase 
D)  Endonuclease

Question 3

What is the function of the item marked y in the illustration?

Accepted Answer

A)  Inactivation of the repressor protein. 
B)  Hydrolysis of lactose to galactose and glucose. 
C)  Activation of the repressor protein. 
D)  Transcription of the structural genes. 
A)  Inactivation of the repressor protein. 
B)  Hydrolysis of lactose to galactose and glucose. 
C)  Activation of the repressor protein. 
D)  Transcription of the structural genes.

Question 4

What structure is labeled z in the illustration?

Accepted Answer

A)  DNA polymerase I 
B)  DNA ligase 
C)  Photolyase 
D)  Endonuclease 
A)  DNA polymerase I 
B)  DNA ligase 
C)  Photolyase 
D)  Endonuclease

Question 5

Which of the following best describes how the lac operon in E. coli works? (Select all that apply)

Accepted Answer

A)  The lac operon controls the expression of enzymes needed to transport lactose into the cell and break it down into glucose and galactose. 
B)  When no lactose is present the repressor blocks transcription of structural genes that code for enzymes that split apart lactose into simple sugars. 
C)  When lactose is present the repressor is activated thereby permitting the production of enzymes that break up lactose. 
D)  When the repressor is active, it binds to the promotor sequence which blocks binding of RNA polymerase to the operator sequence. 
A)  The lac operon controls the expression of enzymes needed to transport lactose into the cell and break it down into glucose and galactose. 
B)  When no lactose is present the repressor blocks transcription of structural genes that code for enzymes that split apart lactose into simple sugars. 
C)  When lactose is present the repressor is activated thereby permitting the production of enzymes that break up lactose. 
D)  When the repressor is active, it binds to the promotor sequence which blocks binding of RNA polymerase to the operator sequence.

Question 6

The DNA strand that is used as pattern for mRNA using complementary base pairing ________.

Accepted Answer

A)  promoter region 
B)  terminator 
C)  coding strand 
D)  template strand 
A)  promoter region 
B)  terminator 
C)  coding strand 
D)  template strand

Question 7

Comparative genomic analysis has shown that genetic islands of genes related to an organism's ________ are commonly shared between pathogens.

Accepted Answer

A)  pathogenicity 
B)  cell wall structure 
C)  avoiding phagocytosis 
D)  attachment to a host cell 
A)  pathogenicity 
B)  cell wall structure 
C)  avoiding phagocytosis 
D)  attachment to a host cell

Question 8

The process shown below is ________. (Select all that apply)

Accepted Answer

A)  gel electrophoresis 
B)  PCR 
C)  indirect ELISA test 
D)  direct ELISA test 
A)  gel electrophoresis 
B)  PCR 
C)  indirect ELISA test 
D)  direct ELISA test

Question 9

The bacterial colonies marked x are ________.

Accepted Answer

A)  colonies of spontaneous his+ revertants 
B)  colonies of mutagen-induced his+ revertants 
C)  his- colonies which grew on the small amount of histidine add to the plate 
D)  his+ colonies of E. coli 
A)  colonies of spontaneous his+ revertants 
B)  colonies of mutagen-induced his+ revertants 
C)  his- colonies which grew on the small amount of histidine add to the plate 
D)  his+ colonies of E. coli

Question 10

Induced mutations can occur as a result of ________. (Select all that apply)

Accepted Answer

A)  chemicals that alter the structure of purines or pyrimidines so they no longer form complementary base pairs 
B)  nonionizing radiation causing formation of adenine dimers 
C)  chemicals that add a functional group to nucleotides that distort their structure and cause errors during replication or repair 
D)  ionizing radiation damaging DNA by creating reactive ions that chemically alter nucleotides 
A)  chemicals that alter the structure of purines or pyrimidines so they no longer form complementary base pairs 
B)  nonionizing radiation causing formation of adenine dimers 
C)  chemicals that add a functional group to nucleotides that distort their structure and cause errors during replication or repair 
D)  ionizing radiation damaging DNA by creating reactive ions that chemically alter nucleotides

Question 11

Transformation is ________.

Accepted Answer

A)  genes transferred from bacterium to bacterium via a bacteriophage 
B)  movement and insertion of DNA segments to new positions within chromosome or plasmid 
C)  naked DNA from the environment is taken up by a bacterium 
D)  formation of a sex pilus allows transfer of a portion of chromosome or plasmid 
A)  genes transferred from bacterium to bacterium via a bacteriophage 
B)  movement and insertion of DNA segments to new positions within chromosome or plasmid 
C)  naked DNA from the environment is taken up by a bacterium 
D)  formation of a sex pilus allows transfer of a portion of chromosome or plasmid

Question 12

Which of the following descriptions about gel electrophoresis of DNA are correct? (Select all that apply)

Accepted Answer

A)  DNA molecules are separated according to the number of base pairs they contain. 
B)  Large DNA molecules travel through the gel more quickly. 
C)  DNA fragments are pulled toward the end of the gel with a negative charge. 
D)  DNA separated in the gel must be stained with dyes in order to be visualized. 
A)  DNA molecules are separated according to the number of base pairs they contain. 
B)  Large DNA molecules travel through the gel more quickly. 
C)  DNA fragments are pulled toward the end of the gel with a negative charge. 
D)  DNA separated in the gel must be stained with dyes in order to be visualized.

Question 13

A plasmid ________.

Accepted Answer

A)  is synthesized from part of the chromosome 
B)  is a small, self-replicating rings of DNA found in some bacteria 
C)  codes for the entire genetic makeup of an organism 
D)  are sets of three nucleotides making up RNA 
A)  is synthesized from part of the chromosome 
B)  is a small, self-replicating rings of DNA found in some bacteria 
C)  codes for the entire genetic makeup of an organism 
D)  are sets of three nucleotides making up RNA

Question 14

What step of the elongation of protein synthesis preceded the illustration shown?

Accepted Answer

A)  Aminoacyl-tRNA selection 
B)  Translocation 
C)  Peptide transfer 
D)  Removal of an unacylated tRNA from the E site 
A)  Aminoacyl-tRNA selection 
B)  Translocation 
C)  Peptide transfer 
D)  Removal of an unacylated tRNA from the E site

Question 15

Which statement best defines a mutation?

Accepted Answer

A)  A mutation is a change in the amino acid sequence of a gene. 
B)  A mutation is a change in the amino acid sequence of a protein. 
C)  A mutation is a change in the nucleotide sequence of a gene. 
D)  A mutation is a change in the nucleotide sequence of DNA. 
A)  A mutation is a change in the amino acid sequence of a gene. 
B)  A mutation is a change in the amino acid sequence of a protein. 
C)  A mutation is a change in the nucleotide sequence of a gene. 
D)  A mutation is a change in the nucleotide sequence of DNA.

Question 16

What process is shown in the illustration?

Accepted Answer

A)  Nucleotide excision repair of a thymine dimer. 
B)  DNA replication. 
C)  Photolyase repair of a thymine dimer. 
D)  DNA polymerase I repair of a thymine dimer. 
A)  Nucleotide excision repair of a thymine dimer. 
B)  DNA replication. 
C)  Photolyase repair of a thymine dimer. 
D)  DNA polymerase I repair of a thymine dimer.

Question 17

Which of the following describes the Ames Test? (Select all that apply)

Accepted Answer

A)  It measures the mutagenic potential of achemical compounds. 
B)  It provides an initial screen for potential carcinogens. 
C)  Uses a strain of Salmonella typhimurium that cannot make the amino acid Methionine. 
D)  The potential mutagen is mixed with a pancreatic extract. 
A)  It measures the mutagenic potential of achemical compounds. 
B)  It provides an initial screen for potential carcinogens. 
C)  Uses a strain of Salmonella typhimurium that cannot make the amino acid Methionine. 
D)  The potential mutagen is mixed with a pancreatic extract.

Question 18

________ participates in various regulatory functions.

Accepted Answer

A)  mRNA 
B)  tRNA 
C)  rRNA 
D)  miRNA 
A)  mRNA 
B)  tRNA 
C)  rRNA 
D)  miRNA

Question 19

What structure is labeled x in the illustration?

Accepted Answer

A)  DNA polymerase I 
B)  DNA ligase 
C)  Photolyase 
D)  Endonuclease 
A)  DNA polymerase I 
B)  DNA ligase 
C)  Photolyase 
D)  Endonuclease

Exam 10: Microbial Genetics and Genetic Engineering

Which of the following is the most frequently used method of horizontal gene transfer used by bacteria?

What structure is labeled y in the illustration?

What is the function of the item marked y in the illustration?

What structure is labeled z in the illustration?

Which of the following best describes how the lac operon in E. coli works? (Select all that apply)

The DNA strand that is used as pattern for mRNA using complementary base pairing ________.

Comparative genomic analysis has shown that genetic islands of genes related to an organism's ________ are commonly shared between pathogens.

The process shown below is ________. (Select all that apply)

The bacterial colonies marked x are ________.

Induced mutations can occur as a result of ________. (Select all that apply)

Transformation is ________.

Which of the following descriptions about gel electrophoresis of DNA are correct? (Select all that apply)

A plasmid ________.

What step of the elongation of protein synthesis preceded the illustration shown?

Which statement best defines a mutation?

What process is shown in the illustration?

Which of the following describes the Ames Test? (Select all that apply)

________ participates in various regulatory functions.

What structure is labeled x in the illustration?

Microbial World

An Introduction to the Chemical Basis of Life

The Biochemistry of Macromolecules

Microscopy

Prokaryote Organisms

Eukaryotic Cells

Eukaryotic Organisms

Viruses and Infectious Particles

Metabolism

Microbial Growth and Control

Antimicrobial Agents

Innate Immunity

Adaptive Immunity

Vaccination, Immunoassays, and Immune Disorders

Microbial Pathogenesis

Epidemiology and Infection Control

Diseases of the Respiratory System

Diseases of the Skin and Eyes

Diseases of the Gastrointestinal System

Diseases of the Urogenital System

Diseases of the Nervous System

Diseases of the Cardiovascular and Lymphatic Systems

Environmental and Industrial Microbiology

Filters