Question 1

A viroid is a(n)

Accepted Answer

A)  provirus. 
B)  infectious protein. 
C)  capsid without nucleic acid. 
D)  complete, infectious virus particle. 
E)  infectious piece of RNA without a capsid. 
A)  provirus. 
B)  infectious protein. 
C)  capsid without nucleic acid. 
D)  complete, infectious virus particle. 
E)  infectious piece of RNA without a capsid.

Question 2

Bacteriophages and animal viruses do NOT differ significantly in which one of the following steps?

Accepted Answer

A)  attachment 
B)  uncoating 
C)  biosynthesis 
D)  penetration 
E)  release 
A)  attachment 
B)  uncoating 
C)  biosynthesis 
D)  penetration 
E)  release

Question 3

A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient?

Accepted Answer

A)  The virus is infecting cells and then releasing only small amounts of virus. 
B)  The virus is incorporating its nucleic acid with that of the patientʹs cells. 
C)  The virus is slowly killing the patientʹs cells. 
D)  The virus is causing the death of the infected cells in the patient. 
E)  The virus is not killing any cells in the host. 
A)  The virus is infecting cells and then releasing only small amounts of virus. 
B)  The virus is incorporating its nucleic acid with that of the patientʹs cells. 
C)  The virus is slowly killing the patientʹs cells. 
D)  The virus is causing the death of the infected cells in the patient. 
E)  The virus is not killing any cells in the host.

Question 4

Oncogenic viruses

Accepted Answer

A)  have no effect on the host cell. 
B)  cause acute infections. 
C)  are genetically unstable. 
D)  cause tumors to develop. 
E)  are lytic viruses that kill the host cell. 
A)  have no effect on the host cell. 
B)  cause acute infections. 
C)  are genetically unstable. 
D)  cause tumors to develop. 
E)  are lytic viruses that kill the host cell.

Question 5

A virusʹs ability to infect an animal cell depends primarily upon the

Accepted Answer

A)  presence of pili on the host cell wall. 
B)  enzymatic activity of a host cell. 
C)  host cellʹs ability to phagocytize viral particles. 
D)  presence of receptor sites on the cell membrane. 
E)  type of viral nucleic acid. 
A)  presence of pili on the host cell wall. 
B)  enzymatic activity of a host cell. 
C)  host cellʹs ability to phagocytize viral particles. 
D)  presence of receptor sites on the cell membrane. 
E)  type of viral nucleic acid.

Question 6

Bacteriophages are used as vectors in genetic engineering to insert new genes into bacteria. Describe the process that makes this genetic recombination possible.

Accepted Answer

Bacteriophages, or viruses that infect b

Question 7

Assume you have isolated an unknown virus. This virus has a single, positive sense strand of RNA, and possesses an envelope. To which group does it most likely belong?

Accepted Answer

A)  togavirus 
B)  retrovirus 
C)  picornavirus 
D)  herpesvirus 
E)  papovavirus 
A)  togavirus 
B)  retrovirus 
C)  picornavirus 
D)  herpesvirus 
E)  papovavirus

Question 8

What contributes to antigenic shift in influenza viruses?

Accepted Answer

A)  ease of virus transmission 
B)  attachment spikes 
C)  worldwide distribution of the virus 
D)  a segmented genome 
E)  different virus subtypes 
A)  ease of virus transmission 
B)  attachment spikes 
C)  worldwide distribution of the virus 
D)  a segmented genome 
E)  different virus subtypes

Question 9

The most conclusive evidence that viruses cause cancers is provided by

Accepted Answer

A)  finding oncogenes in viruses. 
B)  some liver cancer patients having had hepatitis. 
C)  cancer following injection of cell-free filtrates. 
D)  the presence of antibodies against viruses in cancer patients. 
E)  treating cancer with antibodies. 
A)  finding oncogenes in viruses. 
B)  some liver cancer patients having had hepatitis. 
C)  cancer following injection of cell-free filtrates. 
D)  the presence of antibodies against viruses in cancer patients. 
E)  treating cancer with antibodies.

Question 10

A persistent infection is one in which

Accepted Answer

A)  the virus remains in equilibrium with the host without causing a disease. 
B)  host cells are transformed. 
C)  host cells are gradually lysed. 
D)  the disease process occurs gradually over a long period. 
E)  viral replication is unusually slow. 
A)  the virus remains in equilibrium with the host without causing a disease. 
B)  host cells are transformed. 
C)  host cells are gradually lysed. 
D)  the disease process occurs gradually over a long period. 
E)  viral replication is unusually slow.

Question 11

Which one of the following steps does NOT occur during multiplication of a picornavirus?

Accepted Answer

A)  synthesis of DNA 
B)  synthesis of - strands of RNA 
C)  synthesis of viral proteins 
D)  synthesis of + strands of RNA 
E)  None of the answers is correct. 
A)  synthesis of DNA 
B)  synthesis of - strands of RNA 
C)  synthesis of viral proteins 
D)  synthesis of + strands of RNA 
E)  None of the answers is correct.

Question 12

A clear area against a confluent ʺlawnʺ of bacteria is called a

Accepted Answer

A)  cell lysis. 
B)  rash. 
C)  plaque. 
D)  pock. 
E)  phage. 
A)  cell lysis. 
B)  rash. 
C)  plaque. 
D)  pock. 
E)  phage.

Question 13

Dogs do not get measles because their cells lack the correct receptor sites for that virus.

Accepted Answer

A) True 
 B)False

Question 14

Which of the following is necessary for replication of a prion?

Accepted Answer

A)  RNA 
B)  DNA polymerase 
C)  lysozyme 
D)  PrPSc 
E)  DNA 
A)  RNA 
B)  DNA polymerase 
C)  lysozyme 
D)  PrPSc 
E)  DNA

Question 15

Which of the following statements is NOT true of lysogeny?

Accepted Answer

A)  It can give infected pathogens the genetic information for toxin production. 
B)  It is a ʺsilentʺ infection; the virus does not replicate. 
C)  Lytic cycle may follow lysogeny. 
D)  Prophage is inserted into the host genome. 
E)  It causes lysis of host cells. 
A)  It can give infected pathogens the genetic information for toxin production. 
B)  It is a ʺsilentʺ infection; the virus does not replicate. 
C)  Lytic cycle may follow lysogeny. 
D)  Prophage is inserted into the host genome. 
E)  It causes lysis of host cells.

Question 16

How is the replication of the viral genome of retroviruses unique among the viruses?

Accepted Answer

The replication of the viral genome of r

Question 17

Glycoprotein spikes are found on the capsids of all viruses.

Accepted Answer

A) True 
 B)False

Question 18

Generally, in an infection caused by a DNA-containing virus, the host animal cell supplies all of the following EXCEPT

Accepted Answer

A)  nucleotides. 
B)  DNA polymerase. 
C)  RNA polymerase. 
D)  tRNA. 
E)  None of the answers are correct; all of these are supplied by the host animal cell. 
A)  nucleotides. 
B)  DNA polymerase. 
C)  RNA polymerase. 
D)  tRNA. 
E)  None of the answers are correct; all of these are supplied by the host animal cell.

Question 19

An envelope is acquired during which of the following steps?

Accepted Answer

A)  penetration 
B)  adsorption 
C)  release 
D)  biosynthesis 
E)  uncoating 
A)  penetration 
B)  adsorption 
C)  release 
D)  biosynthesis 
E)  uncoating

Question 20

How do all viruses differ from bacteria?

Accepted Answer

A)  Viruses are not composed of cells. 
B)  Viruses are filterable. 
C)  Viruses are obligate intracellular parasites. 
D)  Viruses do not have any nucleic acid. 
E)  Viruses do not reproduce. 
A)  Viruses are not composed of cells. 
B)  Viruses are filterable. 
C)  Viruses are obligate intracellular parasites. 
D)  Viruses do not have any nucleic acid. 
E)  Viruses do not reproduce.

Exam 13: Viruses, Viroids, and Prions

A viroid is a(n)

Bacteriophages and animal viruses do NOT differ significantly in which one of the following steps?

A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient?

Oncogenic viruses

A virusʹs ability to infect an animal cell depends primarily upon the

Bacteriophages are used as vectors in genetic engineering to insert new genes into bacteria. Describe the process that makes this genetic recombination possible.

Assume you have isolated an unknown virus. This virus has a single, positive sense strand of RNA, and possesses an envelope. To which group does it most likely belong?

What contributes to antigenic shift in influenza viruses?

The most conclusive evidence that viruses cause cancers is provided by

A persistent infection is one in which

Which one of the following steps does NOT occur during multiplication of a picornavirus?

A clear area against a confluent ʺlawnʺ of bacteria is called a

Dogs do not get measles because their cells lack the correct receptor sites for that virus.

Which of the following is necessary for replication of a prion?

Which of the following statements is NOT true of lysogeny?

How is the replication of the viral genome of retroviruses unique among the viruses?

Glycoprotein spikes are found on the capsids of all viruses.

Generally, in an infection caused by a DNA-containing virus, the host animal cell supplies all of the following EXCEPT

An envelope is acquired during which of the following steps?

How do all viruses differ from bacteria?

The Microbial World and You

Chemical Principles

Observing Microorganisms Through a Microscope

Functional Anatomy of Prokaryotic and Eukaryotic Cells

Microbial Metabolism

Microbial Growth

The Control of Microbial Growth

Microbial Genetics

Biotechnology and Dna Technology

Classification of Microorganisms

The Prokaryotes: Domains Bacteria and Archaea

The Eukaryotes: Fungi, Algae, Protozoa, and Helminths

Principles of Disease and Epidemiology

Microbial Mechanisms of Pathogenicity

Innate Immunity: Nonspecific Defenses of the Host

Adaptive Immunity: Specific Defenses of the Host

Practical Applications of Immunology

Disorders Associated With the Immune System

Antimicrobial Drugs

Microbial Diseases of the Skin and Eyes

Microbial Diseases of the Nervous System

Microbial Diseases of the Cardiovascular and Lymphatic Systems

Microbial Diseases of the Respiratory System

Microbial Diseases of the Digestive System

Microbial Disease of the Urinary and Reproductive Systems

Environmental Microbiology

Applied and Industrial Microbiology

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