Question 1

Effective antiviral drugs are usually associated with which of the following properties?

Accepted Answer

A)  interference with viral replication 
B)  prevention of the host from becoming infected 
C)  removal of viral proteins 
D)  removal of viral mRNAs 
A)  interference with viral replication 
B)  prevention of the host from becoming infected 
C)  removal of viral proteins 
D)  removal of viral mRNAs

Question 2

RNA viruses require their own supply of certain enzymes because

Accepted Answer

A)  host cells rapidly destroy the viruses. 
B)  host cells lack enzymes that can replicate the viral genome. 
C)  these enzymes translate viral mRNA into proteins. 
D)  these enzymes penetrate host cell membranes. 
A)  host cells rapidly destroy the viruses. 
B)  host cells lack enzymes that can replicate the viral genome. 
C)  these enzymes translate viral mRNA into proteins. 
D)  these enzymes penetrate host cell membranes.

Question 3

Which of the following processes can viruses carry out?

Accepted Answer

A)  They can manufacture their own ATP, proteins, and nucleic acids. 
B)  They can use the host cell to copy themselves and make viral proteins. 
C)  They can use the host cell to copy themselves and then synthesize their own proteins inside the viral capsid. 
D)  They can metabolize food and produce their own ATP. 
A)  They can manufacture their own ATP, proteins, and nucleic acids. 
B)  They can use the host cell to copy themselves and make viral proteins. 
C)  They can use the host cell to copy themselves and then synthesize their own proteins inside the viral capsid. 
D)  They can metabolize food and produce their own ATP.

Question 4

Which of the following human diseases is caused by a virus that requires reverse transcriptase to transcribe its genome inside the host cell?

Accepted Answer

A)  herpes 
B)  AIDS 
C)  smallpox 
D)  influenza 
A)  herpes 
B)  AIDS 
C)  smallpox 
D)  influenza

Question 5

Use the figure to answer the question.
 
In the figure, when new viruses are being assembled at the point marked IV, what mediates the assembly?

Accepted Answer

A)  host cell chaperones 
B)  assembly proteins coded for by the host nucleus 
C)  assembly proteins coded for by the viral genes 
D)  no mediator is required; the new viruses self-assemble 
A)  host cell chaperones 
B)  assembly proteins coded for by the host nucleus 
C)  assembly proteins coded for by the viral genes 
D)  no mediator is required; the new viruses self-assemble

Question 6

Evidence suggests that factors that contribute towards the virulence of E. coli strain O157:H7, a bacterial strain reported to cause several food poisoning deaths, are caused by genes from a virus that infects bacteria. Considering this evidence, which of the following statements most likely explains how the O157:H7 population acquired the genetic variation that distinguishes the strain from harmless E. coli strains, such as those that reside in our intestines?

Accepted Answer

A)  The virus entered the bacterial cell and incorporated its DNA into the bacterial genome, allowing the bacteria's cellular machinery to create new viruses. 
B)  Viral envelope proteins bind to receptors on the bacterial membrane, allowing the viral genetic material to enter the bacterium and become translated into proteins. 
C)  The virus entered the cell and acquired specific genes from the bacteria to increase the virulence of the virus. 
D)  The virus infected the bacterium, and allowed the bacterial population to replicate with a copy of the phage genome in each new bacterium. 
A)  The virus entered the bacterial cell and incorporated its DNA into the bacterial genome, allowing the bacteria's cellular machinery to create new viruses. 
B)  Viral envelope proteins bind to receptors on the bacterial membrane, allowing the viral genetic material to enter the bacterium and become translated into proteins. 
C)  The virus entered the cell and acquired specific genes from the bacteria to increase the virulence of the virus. 
D)  The virus infected the bacterium, and allowed the bacterial population to replicate with a copy of the phage genome in each new bacterium.

Question 7

Some viruses can be crystallized and their structures analyzed. One such virus is yellow mottle virus, which infects beans. This virus has a single-stranded RNA genome containing about 6,300 nucleotides. Its capsid is 25-30 nm in diameter and contains 180 identical capsomeres. If the yellow mottle virus begins its infection of a cell by using its genome as mRNA, which of the following would you expect to be able to measure when analyzing the reproduction of this virus?

Accepted Answer

A)  replication rate 
B)  transcription rate 
C)  translation rate 
D)  formation of new transcription factors 
A)  replication rate 
B)  transcription rate 
C)  translation rate 
D)  formation of new transcription factors

Question 8

Which of the following characteristics correctly describes retroviruses?

Accepted Answer

A)  They are made up of only a single protein. 
B)  They can only reproduce by infecting bacteria. 
C)  They have a single-stranded DNA that acts as a template for DNA synthesis. 
D)  They have a single-stranded RNA that acts as a template for DNA synthesis. 
A)  They are made up of only a single protein. 
B)  They can only reproduce by infecting bacteria. 
C)  They have a single-stranded DNA that acts as a template for DNA synthesis. 
D)  They have a single-stranded RNA that acts as a template for DNA synthesis.

Question 9

Which of the following types of viral genomes could be transcribed using reverse transcriptase?

Accepted Answer

A)  ssRNA 
B)  dsRNA 
C)  ssDNA 
D)  dsDNA 
A)  ssRNA 
B)  dsRNA 
C)  ssDNA 
D)  dsDNA

Question 10

A bacterium is infected with an experimentally constructed bacteriophage composed of the T2 phage protein coat and T4 phage DNA. The new phages produced would have

Accepted Answer

A)  T2 protein and T4 DNA. 
B)  T4 protein and T2 DNA. 
C)  T2 protein and T2 DNA. 
D)  T4 protein and T4 DNA. 
A)  T2 protein and T4 DNA. 
B)  T4 protein and T2 DNA. 
C)  T2 protein and T2 DNA. 
D)  T4 protein and T4 DNA.

Question 11

Which of the following processes can be effective in preventing the onset of viral infection in humans?

Accepted Answer

A)  taking vitamins before being exposed to various viruses 
B)  getting vaccinated to certain viruses 
C)  taking antibiotics to inhibit bacterial growth 
D)  taking drugs that inhibit transcription 
A)  taking vitamins before being exposed to various viruses 
B)  getting vaccinated to certain viruses 
C)  taking antibiotics to inhibit bacterial growth 
D)  taking drugs that inhibit transcription

Question 12

In many ways, the regulation of the genes of a particular group of viruses will be similar to the regulation of the host genes. Therefore, which of the following regulation mechanisms would you expect of the genes of a bacteriophage?

Accepted Answer

A)  regulation via acetylation of histones 
B)  positive control mechanisms rather than negative 
C)  control of more than one gene in an operon 
D)  reliance on transcription activators 
A)  regulation via acetylation of histones 
B)  positive control mechanisms rather than negative 
C)  control of more than one gene in an operon 
D)  reliance on transcription activators

Question 13

Will treating a viral infection with antibiotics affect the course of the infection?

Accepted Answer

A)  No; antibiotics work by inhibiting enzymes specific to bacteria. Antibiotics have no effect on eukaryotic or virally encoded enzymes. 
B)  No; antibiotics do not kill viruses because viruses do not have DNA or RNA. 
C)  Yes; antibiotics activate the immune system, and this decreases the severity of the infection. 
D)  Yes; antibiotics can prevent viral entry into the cell by binding to host-receptor proteins. 
A)  No; antibiotics work by inhibiting enzymes specific to bacteria. Antibiotics have no effect on eukaryotic or virally encoded enzymes. 
B)  No; antibiotics do not kill viruses because viruses do not have DNA or RNA. 
C)  Yes; antibiotics activate the immune system, and this decreases the severity of the infection. 
D)  Yes; antibiotics can prevent viral entry into the cell by binding to host-receptor proteins.

Question 14

Why do RNA viruses appear to have higher rates of mutation?

Accepted Answer

A)  RNA nucleotides are more unstable than DNA nucleotides. 
B)  Replication of their genomes does not involve proofreading. 
C)  RNA viruses can incorporate a variety of nonstandard bases. 
D)  RNA viruses are more sensitive to mutagens. 
A)  RNA nucleotides are more unstable than DNA nucleotides. 
B)  Replication of their genomes does not involve proofreading. 
C)  RNA viruses can incorporate a variety of nonstandard bases. 
D)  RNA viruses are more sensitive to mutagens.

Question 15

A population of viruses with similar characteristics is called a ________.

Accepted Answer

A)  class 
B)  species 
C)  type 
D)  genome 
A)  class 
B)  species 
C)  type 
D)  genome

Question 16

To cause a human pandemic, the H5N1 avian flu virus would have to

Accepted Answer

A)  spread to primates such as chimpanzees. 
B)  develop into a virus with a different host range. 
C)  become capable of human-to-human transmission. 
D)  become much more pathogenic. 
A)  spread to primates such as chimpanzees. 
B)  develop into a virus with a different host range. 
C)  become capable of human-to-human transmission. 
D)  become much more pathogenic.

Question 17

Which of the following viruses would most likely have reverse transcriptase inside them?

Accepted Answer

A)  an RNA-based lytic virus 
B)  an RNA-based lysogenic virus 
C)  a DNA-based lytic virus 
D)  a DNA-based lysogenic virus 
A)  an RNA-based lytic virus 
B)  an RNA-based lysogenic virus 
C)  a DNA-based lytic virus 
D)  a DNA-based lysogenic virus

Question 18

HIV is inactivated in the laboratory after a few minutes of sitting at room temperature, but the flu virus is still active after sitting for several hours. What are the practical consequences of these findings?

Accepted Answer

A)  HIV can be transmitted more easily from person to person than the flu virus. 
B)  The flu virus can be transmitted more easily from person to person than HIV. 
C)  This property of HIV makes it more likely to be a pandemic than the flu virus. 
D)  Disinfecting surfaces is more important to reduce the spread of HIV than the flu. 
A)  HIV can be transmitted more easily from person to person than the flu virus. 
B)  The flu virus can be transmitted more easily from person to person than HIV. 
C)  This property of HIV makes it more likely to be a pandemic than the flu virus. 
D)  Disinfecting surfaces is more important to reduce the spread of HIV than the flu.

Question 19

Which of the following characteristics is typical of the lytic cycle of a bacteriophage?

Accepted Answer

A)  Viral DNA is incorporated into the host genome. 
B)  The viral genome replicates without destroying the host. 
C)  A large number of phages are released at a time. 
D)  The virus-host relationship usually lasts for generations. 
A)  Viral DNA is incorporated into the host genome. 
B)  The viral genome replicates without destroying the host. 
C)  A large number of phages are released at a time. 
D)  The virus-host relationship usually lasts for generations.

Question 20

What is difference between an epidemic and a pandemic?

Accepted Answer

A)  An epidemic is a disease; a pandemic is a treatment. 
B)  An epidemic is restricted to a local region; a pandemic is global. 
C)  An epidemic has low mortality; a pandemic has higher mortality. 
D)  An epidemic is caused by a bacterial infection; a pandemic is caused by a viral infection. 
A)  An epidemic is a disease; a pandemic is a treatment. 
B)  An epidemic is restricted to a local region; a pandemic is global. 
C)  An epidemic has low mortality; a pandemic has higher mortality. 
D)  An epidemic is caused by a bacterial infection; a pandemic is caused by a viral infection.

Exam 19: Viruses

Effective antiviral drugs are usually associated with which of the following properties?

RNA viruses require their own supply of certain enzymes because

Which of the following processes can viruses carry out?

Which of the following human diseases is caused by a virus that requires reverse transcriptase to transcribe its genome inside the host cell?

Use the figure to answer the question. In the figure, when new viruses are being assembled at the point marked IV, what mediates the assembly?

Which of the following characteristics correctly describes retroviruses?

Which of the following types of viral genomes could be transcribed using reverse transcriptase?

A bacterium is infected with an experimentally constructed bacteriophage composed of the T2 phage protein coat and T4 phage DNA. The new phages produced would have

Which of the following processes can be effective in preventing the onset of viral infection in humans?

In many ways, the regulation of the genes of a particular group of viruses will be similar to the regulation of the host genes. Therefore, which of the following regulation mechanisms would you expect of the genes of a bacteriophage?

Will treating a viral infection with antibiotics affect the course of the infection?

Why do RNA viruses appear to have higher rates of mutation?

A population of viruses with similar characteristics is called a ________.

To cause a human pandemic, the H5N1 avian flu virus would have to

Which of the following viruses would most likely have reverse transcriptase inside them?

HIV is inactivated in the laboratory after a few minutes of sitting at room temperature, but the flu virus is still active after sitting for several hours. What are the practical consequences of these findings?

Which of the following characteristics is typical of the lytic cycle of a bacteriophage?

What is difference between an epidemic and a pandemic?

Evolution, the Themes of Biology, and Scientific Inquiry

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Vascular Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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