Unit 3 Topic 9 Enis

A complete viral particle in the extracellular state is called a(n): a. Virion b. Capsid c. Envelope d. Tegument

A

A virus that is unable to replicate within a host cell unless the cell is simultaneously infected with another specific virus is called a(n): a. Satellite b. Prion c. Viroid d. Prophage

A

All of the following might be produced during the biosynthesis phase of a bacteriophage's replication cycle EXCEPT: a. An envelope b. Lysozyme c. DNA polymerase d. Capsomers

A

Animal viruses can be cultured in the laboratory using all of the following EXCEPT: a. Sterile agar plates b. Cell cultures c. Embryonated eggs d. Whole organisms

A

Animal viruses such as chickenpox and herpes viruses can become dormant in infected cells; this phenomenon is known as ____________________. a. Latency b. Metastasis c. Transduction d. Budding

A

Cold sores reappear periodically whenever the infected human host comes under some form of stress. This is because cold sores are caused by a _________ virus. a. Latent b. Conjugative c. Lytic d. Lysogenic

A

Damage to DNA caused by exposure to UV light can sometimes cause a latent prophage to be excised from the bacterial chromosome and return to an active lytic cycle. This process is known as: a. Induction b. Transformation c. Initiation d. Reversion

A

During the intracellular state, a virus exists solely as: a. nucleic acid b. lipid c. Protein d. carbohydrate

A

Prions are infectious agents composed solely of: a. Protein b. ssDNA c. ssRNA d. dsDNA

A

The clumping of red blood cells due to the presence of a virus is called: a. Hemagglutination b. Titer c. Latency d. Cytopathy

A

The delta agent is a defective virus that is incapable of replication unless the host cell is already infected by the hepatitis B virus. The delta agent is thus considered to be a __________. a. Satellite b. Prion c. Prophage d. Bacteriophage

A

The genome of which type of virus can act directly as mRNA and be translated to yield protein? a. +ssRNA b. -ssRNA c. dsDNA d. ssDNA

A

The overall morphology of a bacteriophage is: a. Complex b. Polyhedral c. Icosahedral d. Helical

A

The protective protein shell of a virus is called the: a. Capsid b. Spike c. Envelope d. Tegument

A

Viruses were discovered by: a. Ivanovski b. Twort c. Pasteur d. Watson

A

_________ viruses are among the largest known, approaching the size of the smallest prokaryotic cells. a. Pox b. Influenza c. Corona d. Herpes

A

clear areas on a seeded bacterial lawn resulting from bacteriophage activity are called: a. Plaques b. Induction nodes c. Lytic regions d. Zones of inhibition

A

A bacterium exhibits a phenotypic change after the genome of a prophage has been integrated into its chromosome. This phenomenon is known as: a. Transposition b. Lysogenic conversion c. Conjugation d. Missense mutation

B

All of the following are general characteristics of viruses EXCEPT: a. Smaller than prokaryotes b. Visible by light microscopy c. Contain nucleic acid and protein d. Acellular

B

Antiviral treatments that lack side effects are difficult to develop primarily because ____________________. a. Viruses are nonliving. b. Viruses employ host cells for replication. c. Antiviral drugs cannot enter virus-infected cells. d. Viruses replicate too quickly.

B

Observable cellular abnormalities due to viral infection are called: a. Tropisms b. Cytopathic effects c. Mutations d. Viral morphologies

B

The first virus to be identified was isolated from a ____________________. a. Fungus b. Plant c. Bacterium d. Human

B

The term __________ refers to the number of virions released from an infected host cell when it lyses. a. Load b. Burst size c. Release constant d. Lytic capacity

B

The term ___________ refers to viral specificity for a given type of host cell. a. Selective b. Tropism c. Generalism d. Fastidious

B

Viral genomes are known to exist in all of the following forms EXCEPT: a. Single-stranded DNA b. DNA / RNA hybrid c. Single-stranded RNA d. Double-stranded RNA

B

Viruses lack all of the following EXCEPT: a. Ribosomes b. Nucleic acid c. Organelles d. Cytoplasm

B

Which of the following is an example of a NAAT? a. Observing cells for cytopathic effects b. Using PCR to detect the presence of viral DNA in patient tissue c. Observing hemagglutination d. Performing an ELISA

B

Which of the following viruses creates an intermediary DNA molecule reverse-transcribed from its RNA genome? a. dsDNA b. Retrovirus c. -ssRNA d. dsRNA

B

Why is lysogeny advantageous to a bacteriophage? a. It allows the bacteriophage to infect cells it would not normally infect b. The genetic material of the phage can be passed on to future generations of cells c. It allows the bacteriophage to destroy the host cell's DNA d. It speeds up the viral replication cycle

B

____ utilize antibodies to detect the presence of viruses in patient samples. a. Hemagglutination assays b. EIAs c. NAATs d. Blue/white screening assays

B

_____________ is the phase of the viral growth curve during which viruses have penetrated host cells, but no extracellular virions are yet detectable. a. Inoculation b. Eclipse c. Titer d. Burst

B

Bacteriophages contain a gene encoding for lysozyme, an enzyme that damages bacterial ______________. a. Ribosomes b. DNA c. Cell walls d. Cell membranes

C

During the intracellular state, a virus exists solely as: a. Protein b. Lipid c. Nucleic acid d. Carbohydrate

C

Phages" are: a. Viruses that infect fungi b. Viruses that infect animals c. Viruses that infect bacteria d. Viruses that infect plants

C

Taxonomic groupings of closely-related viral genera are called ____________________, and are given names ending with the suffix -viridae. a. Orders b. Kingdoms c. Families d. Phyla

C

The enzyme lysozyme is critical for which of the stage of the bacteriophage replication cycle? a. Attachment b. Maturation c. Lysis d. Biosynthesis

C

The name "Adenovirus" referrs to a specific viral ___________. a. Order b. Class c. Genus d. Family

C

Using PCR to detect viral DNA in host tissue is an example of a(n): a. Enzyme immunoassay b. Neutralization assay c. NAAT d. Hemagglutination assay

C

Viral spikes are ligands that bind to specific receptors on host cells during the attachment phase of the replication cycle. The spikes of an enveloped animal virus are found on the viral ____________. a. Nucleic acid b. Capsid c. Envelope d. Tail fiber

C

When entering the lysogenic cycle, bacteriophage replication stops after which of the following steps? a. Attachment b. Maturation c. Penetration d. Biosynthesis

C

Which type of virus requires reverse transcriptase during its replication cycle? a. dsRNA virus b. ssDNA virus c. Retrovirus d. -ssRNA virus

C

Why do viruses have to infect host cells? a. They cannot survive outside a host cell. b. They infect host cells in order to cause tumors. c. They are dependent on the host cell's structures and enzymes for their replication. d. They infect host cells in order to steal the cell's genome.

C

"Mad cow" disease is caused by a(n): a. Viroid b. Bacteriophage c. Satellite virus d. Prion

D

A virion that is surrounded by a "stolen" portion of membrane from a host cell is said to be: a. Inactivated b. Encapsulated c. Vesicled d. Enveloped

D

A virus that infects bacteria is called a(n): a. Auxotroph b. Transposon c. Plasmid d. Bacteriophage

D

All of the following diseases are known to be caused by prions EXCEPT: a. Creutzfeldt-Jakob Disease b. "Mad cow" disease c. Scrapie d. Alzheimer's disease

D

Damage to DNA caused by exposure to UV light can sometimes cause a latent prophage to be excised from the bacterial chromosome and return to an active lytic cycle. This process is known as: a. Initiation b. Transformation c. Reversion d. Induction

D

During the lysogenic cycle of bacteriophages, viral DNA is integrated into the host cell's chromosome. This integrated viral DNA is referred to as a: a. Satellite b. Transposon c. Prion d. Prophage

D

Prions cause disease because they interfere with which of the following phenomena? a. Membrane structure b. Replication c. Apoptosis d. Protein folding

D

The process by which some viruses can inadvertently transfer host DNA from one cell to another is called ____________________. a. Transposition b. Conjugation c. Transformation d. Transduction

D

Viruses belong to which of the three domains? a. Archaea b. Bacteria c. Eukarya d. Viruses are not classified within a domain

D

Which of the following groups of viruses is replicated in the cell's nucleus? a. dsRNA viruses b. -ssRNA viruses c. +ssRNA viruses d. dsDNA viruses

D

Observable cellular abnormalities due to viral infection are called: a. Viral morphologies b. Mutations c. Cytopathic effects d. Tropisms

c

All of the following terms are actual viral shapes EXCEPT: a. Complex b. Polyhedral c. Irregular d. Helical

c