Chapter 8 (from quizlet) Flashcards

1
Q

Host specificity of a virus is determined by what?

A

interactions between viral attachment proteins and host cell receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What binding determines the ability of a virus or bacteriophage to specifically attach to a host cell occurs through the interactions of the viral attachment protein with the host cell receptor?

A

the host range

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Antiviral drugs that act at the level of host recognition are designed to do what?

A

prevent virus binding to the cell receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

HIV enters the cell through what type of mechanism?

A

membrane fusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

the influenza virus gains entry into a host cell how?

A

by receptor-mediated endocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do plant viruses often gain entry into host cells?

A

by injury caused by insects to host cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the mode of action for fuzeon? (an antiviral drug that prevents membrane fusion for entry into the cell by HIV)

A

to bind to gp41 membrane fusion protein of HIV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The Baltimore classification scheme classifies viruses based on their mechanism of mRNA synthesis in how many classes?

A

7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Class I viruses, double-stranded DNA viruses, usually utilize what polymerases for mRNA synthesis of DNA replication?

A

host cell DNA-dependent RNA polymerase and host cell DNA-dependent DNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Class III viruses, double-stranded RNA viruses, utilize what polymerase for genome synthesis?

A

viral RNA-dependent RNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Class V viruses, negative sense-stranded RNA viruses, utilize what polymerase for mRNA synthesis?

A

viral RNA-dependent RNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

For most double-stranded DNA eukaryal viruses, DNA replication occurs in the ___ and translation occurs in the ____.

A

nucleus, cytoplams

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A bacteriophage genome that is integrated into the bacterial chromosome is called what?

A

a prophage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Phage lambda is referred to as a temperate phage. What is a temperate phage?

A

A phage that can undergo either a lytic or lysogenic phase of replication.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Protease inhibitors are routinely used in the treatment of an HIV infection to slow down the progression of the disease..How do these inhibitors work?

A

They inhibit the proteolytic modification of the viral capsid to form an infectious virion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How do most enveloped viruses exit the cell?

A

by budding

17
Q

What is the method of assembly of the intact virion of the tobacco mosaic virus?

A

the capsid proteins assemble around the viral nucleic acid

18
Q

Bacteriophage T4 lyses the bacterial host cell for release of newly formed virions. The cell wall of the bacterium is broken down by this virally encoded enzyme..

19
Q

Many antiviral drugs are nucleoside analogs. The nucleoside analogs primarily target what enzyme?

A

viral nucleic acid polymerases

20
Q

AZT is a nucleotide analog used to treat people infected with what?

21
Q

The viral attachment protein specifically binds to a host cell receptor. What are examples of host cell receptors?

A

proteins, glycoproteins, lipopolysacchardes, sialic acids

22
Q

The second step in viral replication is entry. What is the entry for bacteriophage?

A

direct entry of the nucleic acid into the cell

23
Q

Class VII viruses, double-stranded DNA viruses that utilize reverse transcriptase, replicate the genome using what polymerase?

A

host cell DNA-dependent RNA polymerase

24
Q

What is the reason nucleoside analogs are effective against viral nucleic acid polymerases?

A

because viral polymerases have a high affinity for incorporation of the analogs

25
The enzyme ___ has a high affinity for AZT and will incorporate it into a newly synthesized DNA strand. This effectively terminate DNA replication because the incoming nucleotide cannot be bound to AZT.
viral reverse transcriptase
26
An HIV mutant has been identified that is resistant to the drug AZT. most likely the mutation occurred in the viral gene that encodes for what?
reverse transcriptase