Question 1

Which does not refer to the shape of a virus?

Accepted Answer

A)  Bacillus 
B)  Icosahedral 
C)  Helical 
D)  Complex 
E)  These are all virus shapes. 
A)  Bacillus 
B)  Icosahedral 
C)  Helical 
D)  Complex 
E)  These are all virus shapes.

Question 2

What is a defective phage?

Accepted Answer

A)  A virus that has lost some of its genetic material, and therefore cannot infect a new target cell. 
B)  A virus that has lost some of its genetic material, and therefore cannot replicate within a new target cell. 
C)  A virus that lacks the ability to replicate independently of its host cell and cannot survive. 
D)  A virus that cannot attach to its host cell and therefore cannot enter the target cell. 
E)  A virus that lacks a prophage, cannot enter a host cell, and cannot survive. 
A)  A virus that has lost some of its genetic material, and therefore cannot infect a new target cell. 
B)  A virus that has lost some of its genetic material, and therefore cannot replicate within a new target cell. 
C)  A virus that lacks the ability to replicate independently of its host cell and cannot survive. 
D)  A virus that cannot attach to its host cell and therefore cannot enter the target cell. 
E)  A virus that lacks a prophage, cannot enter a host cell, and cannot survive.

Question 3

Prions are

Accepted Answer

A)  a form of RNA virus. 
B)  a form of DNA virus. 
C)  a viroid. 
D)  an infectious protein. 
E)  an infected protein. 
A)  a form of RNA virus. 
B)  a form of DNA virus. 
C)  a viroid. 
D)  an infectious protein. 
E)  an infected protein.

Question 4

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 5

Viruses that infect bacteria are referred to as

Accepted Answer

A)  viralcidens. 
B)  bacteriocidins. 
C)  bacterialogens. 
D)  bacteriophages. 
E)  virophages. 
A)  viralcidens. 
B)  bacteriocidins. 
C)  bacterialogens. 
D)  bacteriophages. 
E)  virophages.

Question 6

A phage that replicates inside the host cell and then lyses its host during its release is a

Accepted Answer

A)  virulent or lytic phage. 
B)  latent phage. 
C)  lysogenic phage. 
D)  dormant phage. 
E)  temperate phage. 
A)  virulent or lytic phage. 
B)  latent phage. 
C)  lysogenic phage. 
D)  dormant phage. 
E)  temperate phage.

Question 7

Attachment of animal viruses to the host cell may be by means of

Accepted Answer

A)  a tail. 
B)  the envelope. 
C)  spikes. 
D)  a capsid. 
E)  a membrane. 
A)  a tail. 
B)  the envelope. 
C)  spikes. 
D)  a capsid. 
E)  a membrane.

Question 8

Why do animal viruses have envelopes and phages rarely do?

Accepted Answer

A)  Since bacteria don't have cell membranes, the bacterial viruses (phages) don't pick them up when they leave the target cells. 
B)  Phages acquire an outer surrounding that is a part of the cell wall of the bacterium they were created in, rather than an outer surrounding of plasma membrane. 
C)  Animal viruses will often use the envelope in order to fuse with the plasma membrane of a new target cell, gaining entry into the cytoplasm. 
D)  Animal viruses build the envelope inside of the target cell as they are being replicated, but before the cell breaks open and releases them into the extracellular environment. The envelope is a remnant of this building process. 
E)  This is a trick question. Plenty of bacteriophages have envelopes that they acquire when they bud through the lipopolysaccharide layer of the bacterial host. 
A)  Since bacteria don't have cell membranes, the bacterial viruses (phages) don't pick them up when they leave the target cells. 
B)  Phages acquire an outer surrounding that is a part of the cell wall of the bacterium they were created in, rather than an outer surrounding of plasma membrane. 
C)  Animal viruses will often use the envelope in order to fuse with the plasma membrane of a new target cell, gaining entry into the cytoplasm. 
D)  Animal viruses build the envelope inside of the target cell as they are being replicated, but before the cell breaks open and releases them into the extracellular environment. The envelope is a remnant of this building process. 
E)  This is a trick question. Plenty of bacteriophages have envelopes that they acquire when they bud through the lipopolysaccharide layer of the bacterial host.

Question 9

In the region of budding, the inside of the cytoplasmic membrane becomes coated with

Accepted Answer

A)  enzymes. 
B)  carbohydrates. 
C)  steroids. 
D)  matrix proteins. 
E)  phospholipids. 
A)  enzymes. 
B)  carbohydrates. 
C)  steroids. 
D)  matrix proteins. 
E)  phospholipids.

Question 10

All bacteriophages must be able to:
1) inject their DNA into the host cell
2) cause a genetic change in the host cell
3) kill the host cell
4) replicate in the absence of a host
5) exit a host cell by extrusion

Accepted Answer

A)  1, 2, and 4 
B)  2 and 3 
C)  1, 4, and 5 
D)  2 only 
E)  1 only 
A)  1, 2, and 4 
B)  2 and 3 
C)  1, 4, and 5 
D)  2 only 
E)  1 only

Question 11

In order to treat cholera, antiviral medication must be given to get rid of the bacteriophage that carries the cholera toxin gene.

Accepted Answer

A) True 
 B)False

Question 12

Entry of bacteriophages and animal viruses into host cells

Accepted Answer

A)  is by endocytosis. 
B)  is by fusion. 
C)  involve entry of the entire nucleocapsid. 
D)  differs because bacteriophages leave the capsid outside the cell, while animal virus entry involves the entry of the whole nucleocapsid. 
E)  differs because animal viruses leave the capsid outside the cell, while bacteriophage entry involves the entry of the whole nucleocapsid. 
A)  is by endocytosis. 
B)  is by fusion. 
C)  involve entry of the entire nucleocapsid. 
D)  differs because bacteriophages leave the capsid outside the cell, while animal virus entry involves the entry of the whole nucleocapsid. 
E)  differs because animal viruses leave the capsid outside the cell, while bacteriophage entry involves the entry of the whole nucleocapsid.

Question 13

The best known chronic infection involves

Accepted Answer

A)  hepatitis B. 
B)  hepatitis A. 
C)  chickenpox. 
D)  herpes. 
E)  influenza. 
A)  hepatitis B. 
B)  hepatitis A. 
C)  chickenpox. 
D)  herpes. 
E)  influenza.

Question 14

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

Accepted Answer

A) True 
 B)False

Question 15

The family to which the Rhinovirus belongs is the

Accepted Answer

A)  Picornaviridae. 
B)  Enterovirus. 
C)  Enteroviridae. 
D)  Picornavirus. 
E)  Rhinoviridae. 
A)  Picornaviridae. 
B)  Enterovirus. 
C)  Enteroviridae. 
D)  Picornavirus. 
E)  Rhinoviridae.

Question 16

Viruses that cause acute infection result in productive infections.

Accepted Answer

A) True 
 B)False

Question 17

Normal tissue taken from animals and prepared immediately as a medium for viral growth is termed a(n)

Accepted Answer

A)  advantageous group. 
B)  monolayer culture. 
C)  primary culture. 
D)  plaque. 
E)  virus culture. 
A)  advantageous group. 
B)  monolayer culture. 
C)  primary culture. 
D)  plaque. 
E)  virus culture.

Question 18

In the replication of phage containing positive-sense DNA,

Accepted Answer

A)  the host's enzymes are used to make dsDNA. 
B)  the host's DNA polymerase uses the phage RNA as a template to make negative-sense DNA. 
C)  a phage-encoded DNA polymerase is used to make negative-sense RNA using the phage positive-sense RNA as a template. 
D)  a phage-encoded DNA polymerase is used to make DNA using the phage positive-sense RNA as a template. 
E)  a phage-encoded RNA polymerase is used to make DNA using the phage positive-sense RNA as a template. 
A)  the host's enzymes are used to make dsDNA. 
B)  the host's DNA polymerase uses the phage RNA as a template to make negative-sense DNA. 
C)  a phage-encoded DNA polymerase is used to make negative-sense RNA using the phage positive-sense RNA as a template. 
D)  a phage-encoded DNA polymerase is used to make DNA using the phage positive-sense RNA as a template. 
E)  a phage-encoded RNA polymerase is used to make DNA using the phage positive-sense RNA as a template.

Question 19

The integration of phage DNA into the bacterial chromosome occurs because of

Accepted Answer

A)  the phage's ability to synthesize an enzyme that integrates its DNA into the host's chromosome. 
B)  the phage's ability to synthesize enzymes that allow it to enter the bacterium. 
C)  similarity in RNA nucleotides in both the phage and the bacterial host. 
D)  the similarity in enzyme metabolism in the phage and the bacterial cell. 
E)  the phage's ability to synthesize enzymes to enter the bacterium AND similar RNA nucleotides in both. 
A)  the phage's ability to synthesize an enzyme that integrates its DNA into the host's chromosome. 
B)  the phage's ability to synthesize enzymes that allow it to enter the bacterium. 
C)  similarity in RNA nucleotides in both the phage and the bacterial host. 
D)  the similarity in enzyme metabolism in the phage and the bacterial cell. 
E)  the phage's ability to synthesize enzymes to enter the bacterium AND similar RNA nucleotides in both.

Question 20

If the infecting phage lacks some critical pieces of DNA necessary for replication, it is called

Accepted Answer

A)  incomplete. 
B)  mutated. 
C)  defective. 
D)  vegetative. 
E)  carcinogenic. 
A)  incomplete. 
B)  mutated. 
C)  defective. 
D)  vegetative. 
E)  carcinogenic.

Exam 13: Viruses, Viroids, and Prions

Which does not refer to the shape of a virus?

What is a defective phage?

Prions are

Viroids characteristically are composed of

Viruses that infect bacteria are referred to as

A phage that replicates inside the host cell and then lyses its host during its release is a

Attachment of animal viruses to the host cell may be by means of

Why do animal viruses have envelopes and phages rarely do?

In the region of budding, the inside of the cytoplasmic membrane becomes coated with

All bacteriophages must be able to: 1) inject their DNA into the host cell 2) cause a genetic change in the host cell 3) kill the host cell 4) replicate in the absence of a host 5) exit a host cell by extrusion

In order to treat cholera, antiviral medication must be given to get rid of the bacteriophage that carries the cholera toxin gene.

Entry of bacteriophages and animal viruses into host cells

The best known chronic infection involves

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

The family to which the Rhinovirus belongs is the

Viruses that cause acute infection result in productive infections.

Normal tissue taken from animals and prepared immediately as a medium for viral growth is termed a(n)

In the replication of phage containing positive-sense DNA,

The integration of phage DNA into the bacterial chromosome occurs because of

If the infecting phage lacks some critical pieces of DNA necessary for replication, it is called

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

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Genitourinary Tract Infections

Microbial Ecology

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

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