Question 1

In contrast to animal viruses and bacteriophages, plant viruses infect cells by mechanisms that do NOT involve specific:

Accepted Answer

A)  receptors 
B)  membranes 
C)  envelopes 
D)  vectors 
E)  hosts 
A)  receptors 
B)  membranes 
C)  envelopes 
D)  vectors 
E)  hosts

Question 2

An icosahedral capsid has how many sides?

Accepted Answer

A)  4 
B)  6 
C)  8 
D)  10 
E)  20 
A)  4 
B)  6 
C)  8 
D)  10 
E)  20

Question 3

To count the number of viruses in a solution, one can perform a plaque assay. Describe how a plaque is generated in the case of a lytic virus and how a virus that does not lyse its host can be detected.

Accepted Answer

A plaque represents the area where one v

Question 4

Some viruses require an RNA-dependent RNA polymerase. What does that mean? Using the same vernacular, what would you call the host cell RNA polymerase (RNA pol)? What would you call reverse transcriptase (RTase)?

Accepted Answer

An RNA-dependent RNA polymerase means th

Question 5

What determines the host range and tropism of a virus?

Accepted Answer

Viruses must attach to specific host cel

Question 6

What are prions and how do they cause disease?

Accepted Answer

Prions are aberrant forms of naturally o

Question 7

Compare and contrast the Baltimore classification of viruses to the proteomic analysis of bacteriophages. Which more accurately reflects the significant impact of phage evolution?

Accepted Answer

The Baltimore classification divides the

Question 8

The flu is an example of:

Accepted Answer

A)  latent infection 
B)  lytic infection 
C)  persistent infection 
D)  transformation 
E)  oncogenic infection 
A)  latent infection 
B)  lytic infection 
C)  persistent infection 
D)  transformation 
E)  oncogenic infection

Question 9

Which of the following steps is NOT part of the life cycle of a lytic phage?

Accepted Answer

A)  Phage DNA is injected into the bacterial cell. 
B)  The phage DNA integrates into the bacterial chromosome. 
C)  Many of copies of phage DNA are made. 
D)  The phage DNA is transcribed and the resulting mRNA is translated to make capsid proteins. 
E)  All of the above steps are part of the life cycle of a lytic phage. 
A)  Phage DNA is injected into the bacterial cell. 
B)  The phage DNA integrates into the bacterial chromosome. 
C)  Many of copies of phage DNA are made. 
D)  The phage DNA is transcribed and the resulting mRNA is translated to make capsid proteins. 
E)  All of the above steps are part of the life cycle of a lytic phage.

Question 10

In bacteriophage T4, the DNA genome is contained in the head, and binding to the host is facilitated by attachment of the:

Accepted Answer

A)  capsid 
B)  neck 
C)  tail fibers 
D)  envelope 
E)  tegument 
A)  capsid 
B)  neck 
C)  tail fibers 
D)  envelope 
E)  tegument

Question 11

__________ of viruses are designated with the suffix viridae.

Accepted Answer

A)  Genera 
B)  Families 
C)  Species 
D)  Orders 
E)  Classes 
A)  Genera 
B)  Families 
C)  Species 
D)  Orders 
E)  Classes

Question 12

__________ gained notoriety when they were implicated in brain infections, such as what is popularly known as mad cow disease.

Accepted Answer

A)  Viroids 
B)  Viruses 
C)  Prions 
D)  Bacteria 
E)  Virions 
A)  Viroids 
B)  Viruses 
C)  Prions 
D)  Bacteria 
E)  Virions

Question 13

Which epidemic is NOT virusborne?

Accepted Answer

A)  AIDS 
B)  bubonic plague 
C)  polio 
D)  SARS 
E)  smallpox 
A)  AIDS 
B)  bubonic plague 
C)  polio 
D)  SARS 
E)  smallpox

Question 14

The proteomic tree of bacteriophages is based on comprehensive analysis of viral:

Accepted Answer

A)  DNAs 
B)  RNAs 
C)  proteins 
D)  capsids 
E)  host range 
A)  DNAs 
B)  RNAs 
C)  proteins 
D)  capsids 
E)  host range

Question 15

What happens to the virus protein coat when a bacterial cell is infected?

Accepted Answer

A)  It enters the host cell with the viral genome. 
B)  It remains on the outside of the host cell. 
C)  It enters the host cell separately from the viral genome. 
D)  It is released to attach to and inject another host cell. 
E)  It becomes part of the host cell membrane. 
A)  It enters the host cell with the viral genome. 
B)  It remains on the outside of the host cell. 
C)  It enters the host cell separately from the viral genome. 
D)  It is released to attach to and inject another host cell. 
E)  It becomes part of the host cell membrane.

Question 16

Within a host, receptor molecules can also determine the __________, or tendency to infect a particular tissue type.

Accepted Answer

A)  tropism 
B)  host range 
C)  virulence 
D)  burst size 
E)  plaque 
A)  tropism 
B)  host range 
C)  virulence 
D)  burst size 
E)  plaque

Question 17

During the eclipse period of a viral infection, why are the virions undetectable in the growth medium?

Accepted Answer

The virions attach to cell sur

Question 18

How is a plaque assay used to count virions in a solution?

Accepted Answer

Dilutions of a solution containing an un

Question 19

Icosahedral viral capsids take the form of a polyhedron with 20 identical __________ faces.

Accepted Answer

A)  helical 
B)  filamentous 
C)  rectangular 
D)  triangular 
E)  asymmetrical 
A)  helical 
B)  filamentous 
C)  rectangular 
D)  triangular 
E)  asymmetrical

Question 20

HIV is classified in a category of slowly replicating retroviruses termed __________.

Accepted Answer

A)  picornaviruses 
B)  papillomaviruses 
C)  oncogenic viruses 
D)  lentiviruses 
E)  pararetroviruses 
A)  picornaviruses 
B)  papillomaviruses 
C)  oncogenic viruses 
D)  lentiviruses 
E)  pararetroviruses

Exam 6: Virus Structure and Function

In contrast to animal viruses and bacteriophages, plant viruses infect cells by mechanisms that do NOT involve specific:

An icosahedral capsid has how many sides?

To count the number of viruses in a solution, one can perform a plaque assay. Describe how a plaque is generated in the case of a lytic virus and how a virus that does not lyse its host can be detected.

Some viruses require an RNA-dependent RNA polymerase. What does that mean? Using the same vernacular, what would you call the host cell RNA polymerase (RNA pol)? What would you call reverse transcriptase (RTase)?

What determines the host range and tropism of a virus?

What are prions and how do they cause disease?

Compare and contrast the Baltimore classification of viruses to the proteomic analysis of bacteriophages. Which more accurately reflects the significant impact of phage evolution?

The flu is an example of:

Which of the following steps is NOT part of the life cycle of a lytic phage?

In bacteriophage T4, the DNA genome is contained in the head, and binding to the host is facilitated by attachment of the:

__________ of viruses are designated with the suffix viridae.

__________ gained notoriety when they were implicated in brain infections, such as what is popularly known as mad cow disease.

Which epidemic is NOT virusborne?

The proteomic tree of bacteriophages is based on comprehensive analysis of viral:

What happens to the virus protein coat when a bacterial cell is infected?

Within a host, receptor molecules can also determine the __________, or tendency to infect a particular tissue type.

During the eclipse period of a viral infection, why are the virions undetectable in the growth medium?

How is a plaque assay used to count virions in a solution?

Icosahedral viral capsids take the form of a polyhedron with 20 identical __________ faces.

HIV is classified in a category of slowly replicating retroviruses termed __________.

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Molecular Techniques and Biotechnology

Energetics and Catabolism

Respiration, Lithotrophy, and Photolysis

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes and the Global Environment

Human Microbiota and Nonspecific Host Defenses

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Chemotherapy

Clinical Microbiology and Epidemiology

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