Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Disease and Defense > Virus Structure and Function > Flashcards

Virus Structure and Function Flashcards

1
Q

What is a virus?

A

Submicroscopic, obligate intracellular parasite that is not alive. They do not grow or undergo division.

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

What is the three part strategy for survival?

A
  1. They house genome in capsid.
  2. Genome contains all information for initiation and completion of infectious cycle.
  3. Establish relationship (benign or lethal) with host.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define: Classical System

A 
Viruses grouped according to their shared physical properties. Such as:
Nature of genetic material (RNA and DNA)
Symmetry of capsid
Naked or Enveloped
Dimensions of capsid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define: Baltimore

A

Based on central Dogma: DNA to RNA to Protein (how do they produce RNA)

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

(+) strand mRNA

A

Translatable open reading frame. Ribosome-ready.

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

First key principle of viral genome

A

Small, finite number of nucleic acid copying strategies.

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

Second key principle of viral genome

A

Function of viral genome is to make mRNA.

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

What are the seven classes of viral genome configuration?

A
  1. dsDNA
  2. ssDNA
  3. gapped circular DNA
  4. dsRNA
  5. ss(+)RNA
  6. ss(-)RNA
  7. ss(+) RNA with DNA intermediate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the three functions of virion proteins?

A
  1. Protection of the genome
  2. Delivery of the genome
  3. Mediate interactions with the host
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Name some characteristics of virus particles.

A

Symmetrical arrangement (helical or icosahedral), non-covalent, highly conserved, and identical bonds between identical subunits.

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

Which of the following symmetrical arrangements (helical or icosahedral) infect all forms of life?

A

Helical

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

What is the icosahedral capsid symmetry pattern?

Are they covalent or noncovalent interactions?

A

2-, 3-, 5-fold symmetry

Noncovalent

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

Enveloped virus membranes are made up of lipid bilayers and glycoproteins. Which is derived from the host and which is from the virus?

A

Glycoproteins are viral and lipid bilayer is derived from the host.

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

What are three sources of lipid bilayers for viral envelopes?

A
  1. Plasma membrane
  2. Golgi Apparatus
  3. Endoplasmic Reticulum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Name three roles of glycoproteins found in viral envelopes.

A
  1. Entry and host range determination
  2. Assembly and egress
  3. Evasion from the vertebrate immune system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define eclipse period in viral growth.

A

Period of time after virus absorption where no infectious virus is detectable inside or outside of the cell.

17
Q

Define latent period in viral growth.

A

The time it takes from the initiation of infection to the release of new infectious virus particles from the cell.

18
Q

Name the events that occur in the latent period.

A
  1. Attachment
  2. Entry and Uncoating
  3. Gene expression
  4. Genome replication
  5. Assembly and egress
19
Q

Give two examples of target receptors for viral attachment.

A
  1. Membrane proteins

2. Carbohydrates (less specific)

20
Q

True or False: Entry of a virus is energy dependent.

A

Yes! The host cell must be metabolically active.

21
Q

Define uncoating

A

Viral capsid is completely or partially removed and viral genome is exposed.

22
Q

True or False- gapped DNA can be transcribed directly without any further modification.

A

FALSE. Gaps must be filled before genes can be transcribed.

23
Q

Which enzyme transcribes viral DNA? Is it derived from host or virus?

A

RNA polymerase II and is host derived.

24
Q

What enzyme is common to all RNA viruses?

A

RNA-dependent RNA polymerase (RdRp)

25
Q

What pathway does the following genome need to take in order to be translated: (+) stranded RNA viruses

A

Can be directly translated

26
Q

What pathway does the following genome need to take in order to be translated: (-) stranded RNA viruses

A

(-) stranded RNA viruses to (+) stranded RNA viruses

27
Q

What pathway does the following genome need to take in order to be translated: dsDNA

A

(-) strand DNA to (+) stranded RNA viruses

28
Q

What pathway does the following genome need to take in order to be translated: Retroviruses [(+) stranded RNA viruses with DNA intermediate]

A

(+) stranded RNA viruses to dsDNA to incorporation into host genome to (+) stranded RNA viruses

29
Q

What enzyme is used for both production fo mRNA and the replication of RNA genomes?

A

RNA-dependent RNA polymerase (RdRp)

30
Q

What enzyme allows for the copying of single stranded RNA genome into double stranded DNA?

A

Reverse transcriptase

31
Q

Describe the two possible strategies dsDNA viruses use to replicate.

A
  1. Replication in the nucleus (dependent on cellular components)
  2. Replication in cytoplasm (independent of cellular components)
32
Q

Where does ssDNA viral replication take place?

A

Inside the host nucleus

33
Q

Does gapped DNA viruses need reverse transcriptase?

A

Yes.

34
Q

What enzyme do RNA viruses use to replicate their genome?

A

RdRp

35
Q

What are the two ways for icosahedral capsids package their genome?

A
  1. Capsid assembles around genome

2. Genome fed into capsid

36
Q

How do naked viruses usually egress?

A

Lysis

37
Q

How do enveloped viruses usually egress?

A

Budding

Disease and Defense (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions