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Flashcards in Chapter 13 Viruses Deck (135)
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1

The term filterable viruses was coined by


A. Beijerinck.

B. Iwanowsky.

C. Twort.

D. d'Herelle.

A. Beijerinck.

2

Crystallization of Tobacco Mosaic Virus was accomplished by


A. Berkley.

B. Stanley.

C. Iwanowsky.

D. Twort.

B. Stanley.

3

Viruses that infect bacteria are referred to as


A. viralcidens.

B. bacteriocidins.

C. bacterialogens.

D. bacteriophages.

D. bacteriophages.

4

A virion is a(n)


A. pathogenic virus.

B. subviral particle.

C. complete, extracellular virus particle.

D. enveloped virus particle.

C. complete, extracellular virus particle.

5

A virion is composed of


A. lipid, protein, and either RNA or DNA.

B. protein and either RNA or DNA.

C. protein and both, RNA and DNA.

D. protein, either RNA or DNA, and possibly lipid.

D. protein, either RNA or DNA, and possibly lipid.

6

The protein coat of a virus


A. is called a capsomere.

B. is called a capsid.

C. protects the nucleic acid.

D. is involved in recognition of host cell receptors.

E. is called a capsid, protects the nucleic acid AND is involved in recognition of host cell receptors.

E. is called a capsid, protects the nucleic acid AND is involved in recognition of host cell receptors.

7

Which does not refer to the shape of a virus?


A. icosahedral (isometric)

B. helical

C. complex

D. bacillus

D. bacillus

8

The shape of the virus is determined by its


A. nucleic acid.

B. capsid.

C. envelope.

D. tail.

B. capsid.

9

The viral envelope closely resembles the


A. prokaryotic cell wall.

B. capsomere.

C. eukaryotic cell membrane.

D. cytoplasm.

C. eukaryotic cell membrane.

10

The protein projections on the surface of a virus that are involved in attachment to the host cell are called


A. suckers.

B. pili.

C. cilia.

D. spikes.

E. hooks.

D. spikes.

11

Outside of living cells, viruses are


A. scavenging glucose.

B. slowly stockpiling ATP from the mitochondria.

C. using cilia to move to the next host.

D. metabolically inert.

D. metabolically inert.

12

Viruses


A. probably keep the numbers of bacteria in check.

B. have no effect on the number of bacteria.

C. increase the number of bacteria.

D. are active in passing DNA from one bacterium to another.

E. probably keep the numbers of bacteria in check AND are active in passing DNA from one bacterium to another.

E. probably keep the numbers of bacteria in check AND are active in passing DNA from one bacterium to another.

13

What part of the attached bacteriophage enters through the host cell wall?


A. the entire virus

B. only the enzymes necessary for replication

C. the nucleic acid

D. the nucleic acid and capsid

E. the capsid only

C. the nucleic acid

14

A phage that replicates inside the host cell and then lyses its host during its release is a


A. virulent or lytic phage.

B. latent phage.

C. lysogenic phage.

D. dormant phage.

A. virulent or lytic phage.

15

The correct order for the stages of a phage infection is:


A. penetration, transcription, attachment, replication of nucleic acid and protein, assembly, release

B. attachment, penetration, transcription, replication of nucleic acid and protein, assembly, release

C. attachment, replication of nucleic acid and protein, penetration, transcription, assembly, release

D. transcription, attachment replication of nucleic acid and protein, assembly, penetration, release

B. attachment, penetration, transcription, replication of nucleic acid and protein, assembly, release

16

Phages that can either replicate and cause cell lysis or can integrate their DNA into the host DNA are called


A. lysogenic phages.

B. lytic phages.

C. virulent phages.

D. segmented phages.

A. lysogenic phages.

17

One of the most intensively studied virulent phages which infects E. coli is


A. T9.

B. T4.

C. beta.

D. gamma.

B. T4.

18

During attachment of phage to E. coli, the phage


A. actively seek out the bacteria.

B. randomly bump into the bacteria.

C. attach to proteins or carbohydrates on the bacterial surface.

D. attach to the bacterial RNA.

E. randomly bump into the bacteria AND attach to proteins or carbohydrates on the bacterial surface.

E. randomly bump into the bacteria AND attach to proteins or carbohydrates on the bacterial surface.

19

What part of the E. coli T4 phage attaches to the host cell receptors?


A. Capsid fragments around the nucleic acid.

B. Protein fibers at the end of the phage tail.

C. Pili of the envelope.

D. Spikes of the envelope.

B. Protein fibers at the end of the phage tail.

20

During penetration of E. coli by the T4 phage


A. lysozyme is used to allow entry of the phage capsid.

B. the tail acts as a "hypodermic needle", injecting the phage DNA into the cell.

C. the protein fibers digest a hole in the cell wall.

D. the bacterial receptor molecules open a hole through the cell wall.

B. the tail acts as a "hypodermic needle", injecting the phage DNA into the cell.

21

Phage-encoded proteins are


A. coded for by host DNA.

B. coded for by phage DNA.

C. proteins normally present in the uninfected cell.

D. early proteins.

E. coded for by phage DNA AND early proteins.

E. coded for by phage DNA AND early proteins.

22

Phage-encoded enzymes are


A. all produced simultaneously.

B. produced in a sequential manner.

C. strictly host enzymes.

D. used to customize the cell for viral production.

E. produced in a sequential manner AND used to customize the cell for viral production.

E. produced in a sequential manner AND used to customize the cell for viral production.

23

Assembly of the T4 phage


A. may involve some self-assembly.

B. may involve the use of scaffolds.

C. is completely self-assembly.

D. is completely dependent on scaffolds.

E. may involve some self-assembly AND may involve the use of scaffolds.

E. may involve some self-assembly AND may involve the use of scaffolds.

24

In the case of T-even phages, the burst size is about


A. 1 per host cell.

B. 5 per host cell.

C. 200 per host cell.

D. 1000 per host cell.

C. 200 per host cell.

25

The time from absorption to release for T-even phage is about


A. 1 minute.

B. 10 minutes.

C. 30 minutes.

D. 1 day.

C. 30 minutes.

26

The replicative form of nucleic acid in filamentous phages is


A. dsDNA.

B. dsRNA.

C. positive ssRNA.

D. negative ssDNA.

A. dsDNA.

27

Filamentous phage


A. only infect E. coli that have pili.

B. only infect E. coli lacking pili.

C. infect E. coli regardless of the presence of pili.

D. do not infect E. coli.

A. only infect E. coli that have pili.

28

Which is a filamentous phage?


A. M13

B. T4

C. lambda

D. phi X174

A. M13

29

The bacterial viruses that are released by a process termed extrusion are called


A. lysogenic viruses.

B. temperate phages.

C. filamentous phages.

D. lambda viruses.

C. filamentous phages.

30

The filamentous phages all contain


A. single-stranded DNA.

B. double-stranded DNA.

C. single-stranded RNA.

D. double-stranded RNA.

A. single-stranded DNA.