Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PMCOL 200 Final > Antiviral Medication > Flashcards

Antiviral Medication Flashcards

1
Q

What are obligate intracellular parasites? Provide an example.

A
  • rely on host biosynthetic machinery to reproduce

- virus

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

Are viruses alive? If not, explain why.

A

viruses are alive and not alive because they cannot reproduce independently

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

When not inside an infected cell, what are viruses called?

A

virions

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

select all that apply…virions consist of:

a) dsDNA
b) ssDNA
c) dsRNA
d) ssRNA

A

virions consist of all 4 options (dsDNA, ssDNA, dsRNA, ssRNA)

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

In a virion, what is a capsid?

A

a protein coat

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

In virions, what is a LIFE capsid?

A

lipid envelope derived from the host cell; may contain antigenic glycoproteins

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

How many proteins do the SIMPLEST viruses encode? How many do most viruses encode? How many do humans encode?

A

simplest –> 4 proteins
most –> 100-200 proteins
humans –> 20,000 proteins

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

Define viral range.

A

viral range = group of cell types (or species) that a virus can infect

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

What is a bacteriophage?

A

bacteriophage = a virus that only infects bacteria

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

What is an animal virus?

A

animal virus = a virus that only infects animals

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

TRUE or FALSE: most animal viruses are not specific to one species

A

FALSE - most animal viruses cannot cross phyla, and some can only infect closely related species

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

What is plant virus?

A

plant virus = a virus that only infects plants

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

What are the 3 virus shapes?

A

1) helical
2) icosahedral
3) complex

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

What is pathogenicity?

A

pathogenicity = the ABILITY of a virus to cause diseases

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

What is virulence?

A

virulence = the DEGREE of pathogenicity

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

what does latency mean, in terms of viral infection?

A

some viruses can remain dormant in organisms and then be triggered at a later time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Define the term “carriers”.

A

carriers = people who are chronically infected, and serve as reservoirs of infectious virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 4 steps of the viral replication cycle? Summarize each step in one word.

A

1) Absorption
2) Penetration
3) Replication
4) Release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What occurs during “absorption” in the viral replication cycle?

A
  • the surface of the virus has proteins which bind to the receptors on the host cell
  • this interaction determines VIRAL RANGE
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What occurs during “penetration” in the viral replication cycle?

A

viral DNA/RNA crosses plasma membrane to cytoplasm or nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What occurs during “replication” of the viral replication cycle?

A

viral DNA/RNA interacts with host transcription and translation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What occurs during “release” in the viral replication cycle?

A

newly synthesized virion particles are released to continue infection cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which step of the viral replication cycle determines viral range in the host cell?

a) replication
b) absorption
c) penetration
d) release

A

b) absorption

24
Q

Most DNA viruses enter the host cell:

a) nucleus
b) cytoplasm

A

a) nucleus

25
Most RNA viruses enter the host cell: a) nucleus b) cytoplasm
b) cytoplasm
26
TRUE or FALSE: Retroviruses have DNA genome.
FALSE - retroviruses have RNA genome
27
Explain the steps that occur during a DNA virus infection.
1) DNA virus enters host cell nucleus 2) viral DNA integrated into host DNA 3) this integrated DNA is transcribed into mRNA by HOST DNA-dependent RNA polymerase 4) the mRNA is translated into viral proteins 5) viral genome is replicated by DNA-dependent DNA polymerase (from host or virus) (DNA --> mRNA --> protein)
28
Explain the steps that occur during a RNA virus infection.
1) dsRNA virus enters cytoplasm of the host cell 2) RNA-DEPENDENT RNA POLYMERASE (made by the virus) acts as a TRANSCRIPTASE (to transcribe/make mRNA) 3) RNA-DEPENDENT RNA POLYMERASE acts as a REPLICASE (to replicate the dsRNA viral genome) 4) translation of the mRNA makes viral proteins (dsRNA --> dsRNA + mRNA --> protein from mRNA)
29
What is a retrovirus?
a virus that has RNA genome that directs formation of DNA
30
Explain the steps that occur during a retrovirus infection.
1) viral REVERSE TRANSCRIPTASE (RNA-dependent DNA polymerase) copies viral RNA into viral DNA 2) viral DNA is integrated into host DNA 3) host DNA is transcribed into mRNA 4) mRNA is transcribed into viral protein (RNA --> DNA --> mRNA --> protein)
31
What 4 forms can vaccinations come in?
1) live-attenuated 2) killed virus (inactivated) 3) viral proteins 4) mRNA (antigens)
32
What are 2 forms of virus prevention/therapy?
1) vaccination | 2) anti-virals
33
Anti-virals are virustatic. What does virustatic mean?
virustatic = only effective against replicating viruses (i.e. do not affect latent viruses)
34
What can combination therapy achieve that most other therapies cannot?
prevent/delay emergence of RESISTANCE to the anti-viral treatment
35
What antiviral is used to treat herpes simplex?
acyclovir
36
Describe the mechanism that acyclovir uses to fight the herpes simplex virus. (hint: consider the structure of acyclovir) Which stage of the viral replication cycle is this drug involved in?
- acyclovir is a nucleoside analog which viruses incorporate into their genomes during replication (i.e. fake DNA binding block) - acyclovir has no OH (OH is necessary to form the DNA backbone) --> DNA CHAIN TERMINATION stage: replication (i. e. acyclovir deactivates newly synthesized viral DNA)
37
which base does acyclovir use? a) adenosine b) thymine c) guanine d) cytosine e) uracil
c) guanine
38
If both the virus and host use guanine in DNA replication, why doesn't acyclovir deactivate the host DNA? (hint: which enzyme is involved?)
- acyclovir must be phosphorylated by herpes THYMIDINE KINASE to be incorporated into viral DNA
39
TRUE or FALSE: thymidine kinase is MORE efficient than the mammalian equivalent enzyme
TRUE
40
What are 3 ways in which herpes simplex can develop resistance to acyclovir?
1) impaired production of viral thymidine kinase 2) altered thymidine kinase substrate specificity (i.e. only phosphorylate thymine and not acyclovir) 3) altered viral DNA polymerase
41
herpes simplex virus is a: a) DNA virus b) RNA virus c) lentivirus
a) DNA virus
42
What does HIV stand for?
human immunodeficiency virus
43
HIV is a: a) DNA virus b) RNA virus c) lentivirus
c) lentivirus (more specifically, a retrovirus)
44
Explain the infection mechanism of HIV.
in general: 1) infect human immune cells (CD4+ T cells) 2) cell-mediated immunity lost 3) replication is constant after the infection step 1 in detail: HIV envelope proteins called gp120 attach to CD4 and CCR5 receptors on T cell surface
45
What does HAART stand for? Explain it's relevance. What virus is it used to treat?
HAART = highly active antiretroviral therapy - use combination of drugs to slow/reverse increases in viral RNA - treat retroviruses like HIV
46
Name the 4 TYPES (classified by mechanism) of antivirals that can be used to treat HIV.
1) entry inhibitors 2) reverse transcriptase inhibitors 3) integrase strand transfer inhibitors (ISTIs) 4) protease inhibitors
47
What is maraviroc used to treat? What is its mechanism? Which stage of the viral replication cycle is this drug involved in?
- treat HIV - CCR5 receptor antagonist (interfere with HIV binding to T cell) - stage: absorption????
48
What are NRTIs? What virus do they treat? What is the mechanism? Which stage of the viral replication cycle is this drug involved in?
- small molecule drugs that are similar to host cell nucleosides - treat HIV - (viral) reverse transcriptase inhibitor --> nucleoside analogue --> lack OH --> CHAIN TERMINATION (i.e. similar to acyclovir mechanism) - stage: replication
49
How are NRTIs similar to acyclovir?
both use chain termination
50
What is an integrase?
integrase = inserts viral DNA into host DNA
51
What is raltegravir? What virus does it treat? What is its mechanism? Which stage of the viral replication cycle is this drug involved in?
- treat HIV - integrase strand transfer inhibitor (prevents integrase from allowing HIV proliferation) - stage: replication
52
What is an aspartate protease?
viral enzyme that cleaves precursor proteins to form mature viral proteins
53
What is the mechanism of a protease inhibitor? What virus can it treat? What other type of antiviral is it used in combination with? Which stage of the viral replication cycle is this drug involved in?
- mechanism: inhibit aspartate proteases (which make mature viral protein) - virus: HIV - used in combination with reverse transcriptase inhibitors - stage: replication
54
What is amantadine (i.e. what is the mechanism)? What is it used to treat? Which stage of the viral replication cycle is this drug involved in?
type of drug: anti-influenza A drug mechanism in general: inhibit viral uncoating of influenza A virus mechanism in detail: - M2 proton ion channel required for acidification of virus core to activate viral RNA transcriptase - amantadine blocks the channel stage: replication????
55
TRUE or FALSE: Amantadine is prophylactic (preventative) against both influenza A and B.
FALSE - amantadine is only prophylactic against influenza A
56
What is zanamavir (i.e. what is its mechanism)? What virus does it treat? Which stage of the viral replication cycle is this drug involved in?
type of drug: anti-influenza A and B drug mechanism in general: impede viral spread mechanism in detail: - neuraminidase cleaves sialic acid from viral proteins, which enables virus to be released from host cell - zanamavir is an inhibitor of neuraminidase which is produced by both influenza A and B stage: release

PMCOL 200 Final (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions