Question 1

You friend wonders whether the same type of virus can cause both an acute and a persistent infection? You answer

Accepted Answer

A)  Yes-the initial infection might be acute but the virus can later become latent by becoming integrated into the host cell genome. 
B)  No-a virus causes either an acute infection or a persistent infection, but never both. 
C)  No-if the initial infection is acute, the virus would have to mutate in the host before being able to cause a persistent infection. 
D)  Yes-acute and persistent infections are really the same thing except that people with persistent infections recover more quickly than those with acute infections. 
E)  Yes-acute and persistent infections are really the same thing except that people with acute infections recover more quickly than those with persistent infections. 
A)  Yes-the initial infection might be acute but the virus can later become latent by becoming integrated into the host cell genome. 
B)  No-a virus causes either an acute infection or a persistent infection, but never both. 
C)  No-if the initial infection is acute, the virus would have to mutate in the host before being able to cause a persistent infection. 
D)  Yes-acute and persistent infections are really the same thing except that people with persistent infections recover more quickly than those with acute infections. 
E)  Yes-acute and persistent infections are really the same thing except that people with acute infections recover more quickly than those with persistent infections. A

Question 2

The receptors to which animal virus attachment proteins usually bind are

Accepted Answer

A)  glycoproteins. 
B)  proteins. 
C)  carbohydrates. 
D)  nucleic acid. 
E)  lipids. 
A)  glycoproteins. 
B)  proteins. 
C)  carbohydrates. 
D)  nucleic acid. 
E)  lipids. A

Question 3

One group of animal viruses that are able to agglutinate red blood cells are the

Accepted Answer

A)  coronaviruses. 
B)  orthomyxoviruses. 
C)  retroviruses. 
D)  reoviruses. 
E)  rhinoviruses. 
A)  coronaviruses. 
B)  orthomyxoviruses. 
C)  retroviruses. 
D)  reoviruses. 
E)  rhinoviruses. B

Question 4

Which of the following BEST describes the protein coat of a virus? It

Accepted Answer

A)  is called a capsomere, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
B)  is called a capsid, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
C)  protects the nucleic acid, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
D)  is called a capsomere, protects the nucleic acid, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
E)  is called a capsid, protects the nucleic acid, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
A)  is called a capsomere, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
B)  is called a capsid, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
C)  protects the nucleic acid, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
D)  is called a capsomere, protects the nucleic acid, AND is involved in the recognition of host cell receptors by non-enveloped viruses. 
E)  is called a capsid, protects the nucleic acid, AND is involved in the recognition of host cell receptors by non-enveloped viruses.

Question 5

Prions

Accepted Answer

A)  consist of a special nucleocapsid. 
B)  are made of protein only. 
C)  are made of RNA only. 
D)  are made of dsRNA and protein. 
E)  consist of proteins and phospholipids. 
A)  consist of a special nucleocapsid. 
B)  are made of protein only. 
C)  are made of RNA only. 
D)  are made of dsRNA and protein. 
E)  consist of proteins and phospholipids.

Question 6

Which statement regarding phage replication is TRUE?

Accepted Answer

A)  A lysogen is a bacterial cell with an integrated prophage. 
B)  When integrated into host DNA, phage DNA is called a virophage. 
C)  Lambda is a good example of a lytic phage. 
D)  Lambda can be a lytic or a temperate phage. 
E)  A lysogen is a virus that has bacterial DNA in it. 
A)  A lysogen is a bacterial cell with an integrated prophage. 
B)  When integrated into host DNA, phage DNA is called a virophage. 
C)  Lambda is a good example of a lytic phage. 
D)  Lambda can be a lytic or a temperate phage. 
E)  A lysogen is a virus that has bacterial DNA in it.

Question 7

Viroids characteristically are composed of

Accepted Answer

A)  ssRNA. 
B)  dsRNA. 
C)  ssDNA. 
D)  dsDNA. 
E)  protein only. 
A)  ssRNA. 
B)  dsRNA. 
C)  ssDNA. 
D)  dsDNA. 
E)  protein only.

Question 8

One of the most intensively studied virulent phages which infects E. coli is ________.

Accepted Answer

A)  T9 
B)  T4 
C)  beta 
D)  gamma 
E)  lambda 
A)  T9 
B)  T4 
C)  beta 
D)  gamma 
E)  lambda

Question 9

The enveloped viruses typically obtain their envelope

Accepted Answer

A)  from the host cytoplasmic membrane as they exit the host. 
B)  from a newly constructed viral-derived membrane. 
C)  from the nuclear membrane as they exit the host. 
D)  from endoplasmic reticulum in the host. 
E)  from the host peptidoglycan as they exit. 
A)  from the host cytoplasmic membrane as they exit the host. 
B)  from a newly constructed viral-derived membrane. 
C)  from the nuclear membrane as they exit the host. 
D)  from endoplasmic reticulum in the host. 
E)  from the host peptidoglycan as they exit.

Question 10

Once inside the host cell, phage DNA

Accepted Answer

A)  is replicated. 
B)  is transcribed. 
C)  may get degraded by bacterial nucleases. 
D)  may integrate into the host chromosome. 
E)  All of the choices are correct. 
A)  is replicated. 
B)  is transcribed. 
C)  may get degraded by bacterial nucleases. 
D)  may integrate into the host chromosome. 
E)  All of the choices are correct.

Question 11

All of the statements about specialized transduction are correct EXCEPT

Accepted Answer

A)  it involves the random transmission of any gene. 
B)  it involves the transfer of a few specific genes. 
C)  it involves a defective virus. 
D)  it only involves genes near the viral DNA integration site. 
E)  it involves temperate phages. 
A)  it involves the random transmission of any gene. 
B)  it involves the transfer of a few specific genes. 
C)  it involves a defective virus. 
D)  it only involves genes near the viral DNA integration site. 
E)  it involves temperate phages.

Question 12

Genetic exchange in segmented viruses that allows a zoonotic virus to infect humans is an example

Accepted Answer

A)  antigenic shift. 
B)  hemagglutination. 
C)  genetic reassortment. 
D)  antigenic drift. 
E)  mutagenesis. 
A)  antigenic shift. 
B)  hemagglutination. 
C)  genetic reassortment. 
D)  antigenic drift. 
E)  mutagenesis.

Question 13

Completed filamentous phages are often found in the cytoplasm of infected bacteria.

Accepted Answer

A) True 
 B)False

Question 14

The phage from which the cholera toxin gene originates is a ________ phage.

Accepted Answer

A)  filamentous 
B)  lytic 
C)  temperate 
D)  Gram-positive 
E)  double-stranded RNA 
A)  filamentous 
B)  lytic 
C)  temperate 
D)  Gram-positive 
E)  double-stranded RNA

Question 15

The nucleocapsid is composed of

Accepted Answer

A)  DNA and RNA and protein. 
B)  DNA or RNA, and protein. 
C)  protein located in the nucleus. 
D)  nucleic acid in the ribosome. 
E)  DNA or RNA, lipid, and protein. 
A)  DNA and RNA and protein. 
B)  DNA or RNA, and protein. 
C)  protein located in the nucleus. 
D)  nucleic acid in the ribosome. 
E)  DNA or RNA, lipid, and protein.

Question 16

The concentration of virus that infects or kills 50% of the host cells is referred to as the

Accepted Answer

A)  LD50 
B)  ID50 
C)  ID100 
D)  LD100 AND ID100 
E)  LD50 AND ID50 
A)  LD50 
B)  ID50 
C)  ID100 
D)  LD100 AND ID100 
E)  LD50 AND ID50

Question 17

Phage-encoded proteins are

Accepted Answer

A)  coded for by host DNA. 
B)  coded for by phage DNA. 
C)  proteins normally present in the uninfected cell. 
D)  early proteins. 
E)  coded for by phage DNA AND early proteins. 
A)  coded for by host DNA. 
B)  coded for by phage DNA. 
C)  proteins normally present in the uninfected cell. 
D)  early proteins. 
E)  coded for by phage DNA AND early proteins.

Question 18

The host range of a virus depends on the presence of host receptor molecules.

Accepted Answer

A) True 
 B)False

Question 19

Why are viroids resistant to nucleases?

Accepted Answer

A)  Having a circular RNA "genome," they are resistant to most exonucleases (that digest the free ends of RNA or DN
A) . 
B)  Having a circular RNA "genome," with no protein shell, they are resistant to the protein-degrading activities of nucleases. 
C)  Nucleases will only digest DNA, not RNA, so viroids are protected. 
D)  Viroids have only been identified in plants. Plant nucleases cannot digest RNA. 
E)  Viroids are composed of single stranded RNA; nucleases only act on double-stranded molecules. 
A)  Having a circular RNA "genome," they are resistant to most exonucleases (that digest the free ends of RNA or DN
A) . 
B)  Having a circular RNA "genome," with no protein shell, they are resistant to the protein-degrading activities of nucleases. 
C)  Nucleases will only digest DNA, not RNA, so viroids are protected. 
D)  Viroids have only been identified in plants. Plant nucleases cannot digest RNA. 
E)  Viroids are composed of single stranded RNA; nucleases only act on double-stranded molecules.

Question 20

What part of the E. coli T4 phage attaches to the host cell receptors?

Accepted Answer

A)  Capsid fragments around the nucleic acid. 
B)  Protein fibers at the end of the phage tail. 
C)  Pili of the envelope. 
D)  Spikes of the envelope. 
E)  Spikes of the cell wall. 
A)  Capsid fragments around the nucleic acid. 
B)  Protein fibers at the end of the phage tail. 
C)  Pili of the envelope. 
D)  Spikes of the envelope. 
E)  Spikes of the cell wall.

Exam 13: Viruses, Viroids, and Prions

You friend wonders whether the same type of virus can cause both an acute and a persistent infection? You answer

The receptors to which animal virus attachment proteins usually bind are

One group of animal viruses that are able to agglutinate red blood cells are the

Which of the following BEST describes the protein coat of a virus? It

Prions

Which statement regarding phage replication is TRUE?

Viroids characteristically are composed of

One of the most intensively studied virulent phages which infects E. coli is ________.

The enveloped viruses typically obtain their envelope

Once inside the host cell, phage DNA

All of the statements about specialized transduction are correct EXCEPT

Genetic exchange in segmented viruses that allows a zoonotic virus to infect humans is an example

Completed filamentous phages are often found in the cytoplasm of infected bacteria.

The phage from which the cholera toxin gene originates is a ________ phage.

The nucleocapsid is composed of

The concentration of virus that infects or kills 50% of the host cells is referred to as the

Phage-encoded proteins are

The host range of a virus depends on the presence of host receptor molecules.

Why are viroids resistant to nucleases?

What part of the E. coli T4 phage attaches to the host cell receptors?

Humans and the Microbial World

The Molecules of Life

Microscopy and Cell Structure

Dynamics of Microbial Growth

Control of Microbial Growth

Microbial Metabolism: Fueling Cell Growth

The Blueprint of Life, From Dna to Protein

Bacterial Genetics

Biotechnology

Identifying and Classifying Microorganisms

The Diversity of Bacteria and Archaea

The Eukaryotic Members of the Microbial World

The Innate Immune Response

The Adaptive Immune Response

Host-Microbe Interactions

Immunological Disorders

Applications of Immune Responses

Epidemiology

Antimicrobial Medications

Respiratory System Infections

Skin Infections

Wound Infections

Digestive System Infections

Blood and Lymphatic Infections

Nervous System Infections

Genitourinary Tract Infections

Microbial Ecology

Environmental Microbiology: Treatment of Water, Wastes, and Polluted Habitats

Food Microbiology

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