Question 1

Advantages provided by the viral envelope include:

Accepted Answer

A) helping viruses infect new cells by fusion of the envelope with the host's plasma membrane. 
B) helping viruses "hide" from attack by the host's immune system. 
C) resistance to extreme pH (below 6 or above 8). 
D) both helping viruses infect new cells by fusion of the envelope with the host's plasma membrane and helping "hide" from attack by the host's immune system. 
A) helping viruses infect new cells by fusion of the envelope with the host's plasma membrane. 
B) helping viruses "hide" from attack by the host's immune system. 
C) resistance to extreme pH (below 6 or above 8). 
D) both helping viruses infect new cells by fusion of the envelope with the host's plasma membrane and helping "hide" from attack by the host's immune system.

Question 2

The most conclusive evidence that viruses cause cancers is provided by:

Accepted Answer

A) the presence of oncogenes in humans 
B) the presence of antibodies against viruses in cancer patients 
C) treating cancer patients with antibiotics 
D) development of a cancer following an injection of viruses 
A) the presence of oncogenes in humans 
B) the presence of antibodies against viruses in cancer patients 
C) treating cancer patients with antibiotics 
D) development of a cancer following an injection of viruses

Question 3

Which of the following structures do viruses use to attach themselves and enter the host cells?

Accepted Answer

A) viral spikes 
B) viral tails 
C) viral particles 
D) viral nucleic acid 
A) viral spikes 
B) viral tails 
C) viral particles 
D) viral nucleic acid

Question 4

Which of the following viruses are known for causing latent infections?

Accepted Answer

A) adenoviruses 
B) herpesviruses 
C) poxviruses 
D) parvoviruses 
A) adenoviruses 
B) herpesviruses 
C) poxviruses 
D) parvoviruses

Question 5

Viruses have some of the properties of cellular life forms.Which of the following is a characteristic of all organisms except viruses?

Accepted Answer

A) presence of a plasma membrane 
B) capable of mutation 
C) ability to reproduce inside a living host 
D) grow in response to their environmental conditions 
A) presence of a plasma membrane 
B) capable of mutation 
C) ability to reproduce inside a living host 
D) grow in response to their environmental conditions

Question 6

Identify the portion of the growth curve that represents the time after penetration to the release of mature phages.

Accepted Answer

A) A 
B) B 
C) C 
A) A 
B) B 
C) C

Question 7

Viral host range refers to the:

Accepted Answer

A) tissue types able to be infected by a virus 
B) number of species that are infected by a virus 
C) number of eukaryotic kingdoms able to be infected by a virus 
D) none of these choices 
A) tissue types able to be infected by a virus 
B) number of species that are infected by a virus 
C) number of eukaryotic kingdoms able to be infected by a virus 
D) none of these choices

Question 8

Viruses are referred to as obligate intracellular parasites because:

Accepted Answer

A) viral DNA inserts itself into host DNA. 
B) they reproduce and then exit the cell. 
C) they use the host's energy to live. 
D) they must use the host's machinery to synthesize components required for assembly into new virus particles. 
A) viral DNA inserts itself into host DNA. 
B) they reproduce and then exit the cell. 
C) they use the host's energy to live. 
D) they must use the host's machinery to synthesize components required for assembly into new virus particles.

Question 9

Much of the information about how viruses work has been gleaned from studying T- even phages that infect:

Accepted Answer

A) bacteria 
B) human cells 
C) mammalian cells 
D) plant cells 
A) bacteria 
B) human cells 
C) mammalian cells 
D) plant cells

Question 10

DNA viruses are grouped into families based on the following characteristics except:

Accepted Answer

A) presence of an envelope 
B) presence of a capsid 
C) whether DNA is single stranded or double stranded 
D) whether DNA is linear or circular 
A) presence of an envelope 
B) presence of a capsid 
C) whether DNA is single stranded or double stranded 
D) whether DNA is linear or circular

Question 11

Some viruses have a lipid bilayer,also known as the viral envelope.The viral envelope is most likely to come from the following source:

Accepted Answer

A) host cell plasma membrane 
B) host membrane-bound organelles 
C) host nucleus 
D) another virus 
A) host cell plasma membrane 
B) host membrane-bound organelles 
C) host nucleus 
D) another virus

Question 12

A latent viral infection is an infection in which:

Accepted Answer

A) viral replication is slow 
B) viruses remain within host cells without ever causing a disease 
C) a viral infection causes a disease progression gradually over a long period 
D) viral replication has stopped but may resume years or decades later upon reactivation 
A) viral replication is slow 
B) viruses remain within host cells without ever causing a disease 
C) a viral infection causes a disease progression gradually over a long period 
D) viral replication has stopped but may resume years or decades later upon reactivation

Question 13

All of the following viruses may stay inside of a cell for many years and remain inactive except:

Accepted Answer

A) herpes simplex 
B) chickenpox 
C) HIV 
D) enterovirus 
A) herpes simplex 
B) chickenpox 
C) HIV 
D) enterovirus

Question 14

Viroids are composed of ______.

Accepted Answer

A) single infectious proteins 
B) double stranded RNA 
C) single-stranded linear DNA 
D) single-stranded circular RNA 
A) single infectious proteins 
B) double stranded RNA 
C) single-stranded linear DNA 
D) single-stranded circular RNA

Question 15

What would be a reasonable number of new phages to expect from one round of viral replication in one cell?

Accepted Answer

A) 2 
B) 100 
C) 1000 
D) 10000 
A) 2 
B) 100 
C) 1000 
D) 10000

Question 16

Which of the following is used by (-)sense RNA viruses such as measles and influenza during their replication cycle?

Accepted Answer

A) synthesize DNA via reverse transcriptase 
B) synthesize a double stranded RNA intermediate 
C) synthesize an RNA:DNA hybrid whose RNA is a (+)strand 
D) synthesize an RNA:DNA hybrid whose DNA is a (-)strand 
A) synthesize DNA via reverse transcriptase 
B) synthesize a double stranded RNA intermediate 
C) synthesize an RNA:DNA hybrid whose RNA is a (+)strand 
D) synthesize an RNA:DNA hybrid whose DNA is a (-)strand

Exam 10: Viruses

Advantages provided by the viral envelope include:

The most conclusive evidence that viruses cause cancers is provided by:

Which of the following structures do viruses use to attach themselves and enter the host cells?

Which of the following viruses are known for causing latent infections?

Viruses have some of the properties of cellular life forms.Which of the following is a characteristic of all organisms except viruses?

Identify the portion of the growth curve that represents the time after penetration to the release of mature phages.

Viral host range refers to the:

Viruses are referred to as obligate intracellular parasites because:

Much of the information about how viruses work has been gleaned from studying T- even phages that infect:

DNA viruses are grouped into families based on the following characteristics except:

Some viruses have a lipid bilayer,also known as the viral envelope.The viral envelope is most likely to come from the following source:

A latent viral infection is an infection in which:

All of the following viruses may stay inside of a cell for many years and remain inactive except:

Viroids are composed of ______.

What would be a reasonable number of new phages to expect from one round of viral replication in one cell?

Which of the following is used by (-)sense RNA viruses such as measles and influenza during their replication cycle?

Scope and History of Microbiology

Fundamentals of Chemistry

Microscopy and Staining

Characteristics of Prokaryotic and Eukaryotic Cells

Essential Concepts of Metabolism

Growth and Culturing of Bacteria

Microbial Genetics

Gene Transfer and Genetic Engineering

An Introduction to Taxonomy: the Bacteria

Eukaryotic Microorganisms and Parasites

Sterilization and Disinfection

Antimicrobial Therapy

Host-Microbe Relationships and Disease Processes

Epidemiology and Nosocomial Infections

Innate Host Defenses

Immunology I: Basic Principles of Adaptive Immunity and Immunization

Immunology Ii: Immunological Disorders and Tests

Diseases of the Skin and Eyes; Wounds and Bites

Urogenital and Sexually Transmitted Diseases

Diseases of the Respiratory System

Oral and Gastrointestinal Diseases

Cardiovascular, lymphatic and Systemic Disease

Diseases of the Nervous System

Environmental Microbiology

Applied Microbiology

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