Who developed a rabies vaccine by separating bacteria from virus using a filter?

Who developed a rabies vaccine by separating bacteria from virus using a filter? 

A. Leewonhoek
B. Koch
C. Pasteur
D. Cohn

Answer: C

Which of the following will not support viral cultivation?

Which of the following will not support viral cultivation? 

A. Live lab animals
B. Embryonated bird eggs
C. Primary cell cultures
D. Continuous cell cultures
E. All of the choices will support viral cultivation

Answer: E

Which of the following occurs during assembly?

Which of the following occurs during assembly? 

A. Nucleocapsid is formed
B. New viral nucleic acid is formed
C. Viral spikes insert in host cell membrane
D. All of the choices occur
E. Only choices A and C occur

Answer: E

Which of the following is not a typical capsid shape?

Which of the following is not a typical capsid shape? 

A. Tetrahedral
B. Complex
C. Helical
D. Icosahedron
E. All of the choices are capsid shapes

Answer: A

Which of the following is not associated with every virus?

Which of the following is not associated with every virus? 

A. Envelope
B. Capsomeres
C. Capsid
D. Nucleic acid
E. Genome

Answer: A

Which of the following is not a characteristic of a transformed cell?

Which of the following is not a characteristic of a transformed cell?

A. Viral nucleic acid integrated into host DNA
B. Decreased growth rate
C. Alterations in chromosomes
D. Changes in cell surface molecules
E. Capacity to divide indefinitely

Answer: B

Which of the following is incorrect about prophages?

Which of the following is incorrect about prophages? 

A. Present when the virus is in lysogeny
B. Formed when viral DNA enters the bacterial chromosome
C. Replicated with host DNA and passed on to progeny
D. Cause lysis of host cells
E. Occur when temperate phages enter host cells

Answer: D

Which of the following is a type of cytopathic effect?

Which of the following is a type of cytopathic effect? 

A. Inclusions in the nucleus
B. Multinucleated giant cells
C. Inclusions in the cytoplasm
D. Cells round up
E. All of the choices are correct

Answer: E

When a bacterium acquires a trait from its temperate phage, it is called

When a bacterium acquires a trait from its temperate phage, it is called 

A. Transformation
B. Lysogenic conversion
C. Viral persistence
D. Transcription
E. Translation

Answer: B

What type of phage enters an inactive prophage stage?

What type of phage enters an inactive prophage stage? 

A. Primary
B. Secondary
C. Temperate
D. Temporary
E. Transformed

Answer: C

What structures are used by bacteriophages to attach to host cell receptors?

What structures are used by bacteriophages to attach to host cell receptors? 

A. Sheath
B. Tail fibers
C. Nucleic acid
D. Capsid head
E. None of the choices are correct

Answer: B

Visible, clear, well-defined patches in a monolayer of virus-infected cells in a culture are called

Visible, clear, well-defined patches in a monolayer of virus-infected cells in a culture are called 

A. Lysogeny
B. Budding
C. Plaques
D. Cytopathic effects
E. Pocks

Answer: C

Viruses with _____ sense RNA contain the correct message for translation, while viruses with _____ sense RNA must first be converted into a correct message.

Viruses with _____ sense RNA contain the correct message for translation, while viruses with _____ sense RNA must first be converted into a correct message. 

A. Positive, negative
B. Negative, positive
C. Primary, secondary
D. Secondary, primary
E. None of the choices are correct

Answer: A

Viruses that infect bacteria are specifically called

Viruses that infect bacteria are specifically called 

A. Viroids
B. Prions
C. Bacteriophages
D. Satellite viruses
E. All of the choices infect bacteria

Answer: C

Viruses that cause infection resulting in alternating periods of activity with symptoms and inactivity without symptoms are called

Viruses that cause infection resulting in alternating periods of activity with symptoms and inactivity without symptoms are called 

A. Latent
B. Oncogenic
C. Prions
D. Viroids
E. Delta agents

Answer: A

Viruses have all the following except

Viruses have all the following except 

A. Definite shape
B. Metabolism
C. Genes
D. Ability to infect host cells
E. Ultramicroscopic size

Answer: B

Viruses attach to their hosts via

Viruses attach to their hosts via 

A. Host glycoproteins
B. Host phospholipids
C. Viral phospholipids
D. Viral flagella
E. All of the choices are correct

Answer: A

Viruses acquire envelopes around their nucleocapsids during

Viruses acquire envelopes around their nucleocapsids during 

A. Replication
B. Assembly
C. Adsorption
D. Release
E. Penetration

Answer: D

Viruses

Viruses 

A. Cannot be seen in a light microscope
B. Are prokaryotic
C. Contain 70S ribosomes
D. Undergo binary fission
E. All of the choices are correct

Answer: A

Virus capsids are made from subunits called

Virus capsids are made from subunits called 

A. Envelopes
B. Spikes
C. Capsomeres
D. Prophages
E. Peplomers

Answer: C

Viral tissue specificities are called

Viral tissue specificities are called 

A. Ranges
B. Virions
C. Receptacles
D. Tropisms
E. Uncoating

Answer: D

Viral nucleic acids include which of the following

Viral nucleic acids include which of the following 

A. Double stranded DNA
B. Single stranded DNA
C. Double stranded RNA
D. Single stranded RNA
E. All of the choices are correct

Answer: E

Uncoating of viral nucleic acid

Uncoating of viral nucleic acid 

A. Does not occur in bacteriophage multiplication
B. Involves enzymatic destruction of the capsid
C. Occurs during penetration in the multiplication cycle
D. Occurs before replication
E. All of the choices are correct

Answer: E

Two noncellular agents, smaller than viruses, are the infectious proteins called _____ and the infectious RNA strands called _____.

Two noncellular agents, smaller than viruses, are the infectious proteins called _____ and the infectious RNA strands called _____. 

A. Prions, capsomeres
B. Virions, prions
C. Viroids, phages
D. Prions, phages
E. Prions, viroids

Answer: E

T-even phages

T-even phages 

A. Include the poxviruses
B. Infect Escherichia coli cells
C. Enter host cells by engulfment
D. Have helical capsids
E. All of the choices are correct

Answer: B

Satellite viruses are

Satellite viruses are 

A. Also called viroids
B. Dependent on other viruses for replication
C. The cause of spongiform encephalopathies
D. Significant pathogens of plants
E. All of the choices are correct

Answer: B

Reverse transcriptase synthesizes

Reverse transcriptase synthesizes 

A. The positive RNA strand from a negative RNA strand
B. A negative RNA strand from a positive RNA strand
C. Viral RNA from DNA
D. Viral DNA from RNA
E. None of the choices are correct

Answer: E

The process of dissolving the envelope and capsid to release the viral nucleic acid is

The process of dissolving the envelope and capsid to release the viral nucleic acid is 

A. Adsorption
B. Penetration
C. Uncoating
D. Synthesis
E. Assembly

Answer: C

The primary purposes of viral cultivation are:

The primary purposes of viral cultivation are: 

A. to isolate and identify viruses in clinical specimens
B. to prepare viruses for vaccines
C. to do detailed research on viral structure, lifestyle, genetics and effects on host cells
D. All of these

Answer: D

Persistent viruses that can reactivate periodically are

Persistent viruses that can reactivate periodically are 

A. Chronic latent viruses
B. Oncoviruses
C. Syncytia
D. Inclusion bodies
E. Cytiopathic

Answer: A

One of the principal capsid shapes is a 20-sided figure with 12 evenly spaced corners referred to as a(n) _____ capsid.

One of the principal capsid shapes is a 20-sided figure with 12 evenly spaced corners referred to as a(n) _____ capsid. 

A. Spiked
B. Complex
C. Icosahedral
D. Helical
E. Buckeyball

Answer: C

Oncogenic viruses include all the following except

Oncogenic viruses include all the following except 

A. Hepatitis B virus
B. Measles virus
C. Papillomavirus
D. HTLVI and HTLVII viruses
E. Epstein-Barr virus

Answer: B

New, non enveloped virus release occurs by

New, non enveloped virus release occurs by 

A. Lysis
B. Budding
C. Exocytosis
D. Both lysis and budding
E. Both budding and exocytosis

Answer: A

A naked virus only has a(n)

A naked virus only has a(n) 

A. Capsid
B. Capsomere
C. Nucleocapsid
D. Envelope
E. Antigenic surface

Answer: C

Mammalian viruses capable of starting tumors are

Mammalian viruses capable of starting tumors are 

A. Chronic latent viruses
B. Oncoviruses
C. Syncytia
D. Inclusion bodies
E. Cytiopathic

Answer: B

Lysogeny refers to

Lysogeny refers to 

A. Altering the host range of a virus
B. Latent state of herpes infections
C. Virion exiting host cell
D. Viral genome inserting into bacterial host chromosome
E. None of the choices are correct

Answer: D

A _____ is the protein shell around the nucleic acid core of a virus.

A _____ is the protein shell around the nucleic acid core of a virus. 

A. Capsomere
B. Capsid
C. Spike
D. Envelope
E. Monolayer

Answer: B

In general, most DNA viruses multiply in the host cell's _____, while most RNA viruses multiply in the host cell's _____.

In general, most DNA viruses multiply in the host cell's _____, while most RNA viruses multiply in the host cell's _____. 

A. Nucleus, cytoplasm
B. Cytoplasm, cell membrane
C. Cell membrane, cytoplasm
D. Cytoplasm, nucleus
E. Nucleus, endoplasmic reticulum

Answer: A

Infectious protein particles are called

Infectious protein particles are called 

A. Viroids
B. Phages
C. Prions
D. Oncogenic viruses
E. Spikes

Answer: C

Infectious naked strands of RNA that affect plants are called

Infectious naked strands of RNA that affect plants are called 

A. Viroids
B. Phages
C. Prions
D. Oncogenic viruses
E. Spikes

Answer: A

Host range is limited by

Host range is limited by 

A. Type of nucleic acid in the virus
B. Age of the host cell
C. Type of host cell receptors on cell membrane
D. Size of the host cell
E. All of the choices are correct

Answer: C

Host cells of viruses include

Host cells of viruses include 

A. Human and other animals
B. Plants and fungi
C. Bacteria
D. Protozoa and algae
E. All of the choices are correct

Answer: E

Helical and icosahedral are terms used to describe the shapes of a virus

Helical and icosahedral are terms used to describe the shapes of a virus 

A. Spike
B. Capsomere
C. Envelope
D. Capsid
E. Core

Answer: D

The event that occurs in bacteriophage multiplication that does not occur in animal virus replication is

The event that occurs in bacteriophage multiplication that does not occur in animal virus replication is 

A. Adsorption to the host cells
B. Injection of only the viral nucleic acid into the host cell
C. Host cell synthesis of viral enzymes and capsid proteins
D. Assembly of nucleocapsids
E. Replication of viral nucleic acid

Answer: B

The envelope of enveloped viruses is

The envelope of enveloped viruses is 

A. Identical to the host plasma membrane
B. Only compose of host endomembrane
C. Always includes spikes
D. Is obtained by viral budding or exocytosis
E. None of the choices are correct

Answer: D

During lysogeny, an inactive prophage state occurs when the viral DNA is inserted into the

During lysogeny, an inactive prophage state occurs when the viral DNA is inserted into the 

A. Host cytoplasm
B. Host nucleus
C. Host nucleolus
D. Host DNA
E. Host cell membrane

Answer: D

Creutzfeld-Jacob disease is

Creutzfeld-Jacob disease is 

A. Caused by a chronic latent virus
B. Initiated by an oncogenic virus
C. Caused by a viroid
D. A spongiform encephalopathy of humans
E. Also called "mad cow disease"

Answer: D

The core of every virus particle always contains

The core of every virus particle always contains 

A. DNA
B. Capsomeres
C. Enzymes
D. DNA and RNA
E. Either DNA or RNA

Answer: E

A common method for cultivating viruses in the lab is to use in vitro systems called _____ cultures.

A common method for cultivating viruses in the lab is to use in vitro systems called _____ cultures.

A. Embryo
B. Cell
C. Plaque
D. Bacteriophage
E. Egg

Answer: B

Cells grown in culture form a(n)

Cells grown in culture form a(n) 

A. Monolayer
B. Bilayer
C. Aggregate
D. Plaque
E. None of the choices are correct

Answer: A

All of the following pertain to virus envelopes except

All of the following pertain to virus envelopes except 

A. Gained as a virus leaves the host cell membrane
B. Gained as a virus leaves the nuclear membrane
C. Contain special virus proteins
D. Help the virus particle attach to host cells
E. Located between the capsid and nucleic acid

Answer: E

The activation of a prophage is called

The activation of a prophage is called 

A. Activation
B. Lysogeny
C. Transformation
D. Induction
E. Adsorption

Answer: D