Question 1

Which of the following best describes an operon in prokaryotic gene regulation?

Accepted Answer

Two or more genes transcribed into a single mRNA under the same regulatory control

Question 2

What is the role of a corepressor in negative control of gene expression in bacteria?

Accepted Answer

It binds to the repressor protein, enabling it to bind DNA and block transcription

Question 3

Which statement about the lac operon is correct?

Accepted Answer

Transcription proceeds when the inducer binds to the repressor, preventing it from binding DNA

Question 4

What is the function of DNA binding proteins in prokaryotic gene regulation?

Accepted Answer

They interact with nucleic acids to regulate transcription

Question 5

Which of the following is a feature of gene regulation in Archaea that is similar to bacteria?

Accepted Answer

Regulation of transcription by promoter and operator regions

Question 6

A bacterial cell uses quorum sensing to regulate gene expression. What is required for quorum sensing to trigger a change in gene expression?

Accepted Answer

Accumulation of signaling molecules above a threshold concentration

Question 7

Which hepatitis virus requires co-infection with another hepatitis virus to cause disease?

Accepted Answer

Hepatitis D

Question 8

What is the main function of hemagglutinin in the influenza virus life cycle?

Accepted Answer

Attachment to the host cell and entry

Question 9

Which of the following mechanisms can increase mRNA stability in a cell?

Accepted Answer

Binding of small RNA that prevents ribonuclease from degrading mRNA

Question 10

What is the effect of a neuraminidase inhibitor on influenza virus infection?

Accepted Answer

It does not stop the virus but prevents its spread in a systematic way

Question 11

Which of the following is true about noncoding RNA?

Accepted Answer

It includes rRNA, tRNA, and signal recognition particle RNA

Question 12

What is the role of a sensor kinase in a two-component regulatory system?

Accepted Answer

It senses environmental signals and phosphorylates a response regulator

Question 13

Which equation best represents the process of allosteric inhibition?

Accepted Answer

$E + I \rightarrow EI$ (where $E$ is enzyme, $I$ is inhibitor, $EI$ is enzyme-inhibitor complex)

Question 14

Which of the following is a plausible consequence of genetic shift in influenza virus?

Accepted Answer

Emergence of new viral strains with altered antigenicity

Question 15

Which of the following is NOT a mechanism by which small RNA can alter translation of mRNA?

Accepted Answer

Directly catalyzing protein synthesis

Question 16

What is a regulon in bacterial gene regulation?

Accepted Answer

A set of operons and/or genes all under control of the same regulatory protein

Question 17

Which of the following best explains why Hepatitis C virus can hide within liver cells?

Accepted Answer

It disrupts pattern recognition receptors (PRRs) like receptors

Question 18

Which statement about the arginine operon is correct?

Accepted Answer

Transcription is blocked when the corepressor binds to the repressor

Question 19

Which of the following is a virulence factor that allows bacteria to sense two different things?

Accepted Answer

Sensor kinase

Question 20

Which equation describes the process of mRNA degradation promoted by small RNA?

Accepted Answer

$mRNA + sRNA ightarrow mRNA	ext{-}sRNA ightarrow 	ext{degradation by ribonuclease}$

Microbial Gene Regulation, Viral Pathogenesis, and Host Interaction: Study Notes

Study Guide - Practice Questions