Intro to Virology

Question 1

Characteristics of Viruses

Answer 1

1. filterable agents
2. reproduce via component assembly
3. Genome- RNA, DNA, both RNA and DNA ss, ds, linear or circular
4. RNA can be sense, antisense, or ambisense

what is ambisense?

Question 2

Viral size correlates with?

Answer 2

genome size and complexity

Question 3

Viral RNA can be

Answer 3

sense, anti-sense, or ambisense

Ambisense viruses contain at least one ambisense RNA segment, i.e. an RNA that is in part of positive and in part of negative polarity. Because of this unique gene organization, one might expect ambisense RNA viruses to borrow expression strategies from both positive and negative RNA viruses.

Question 4

Virion

Answer 4

The virus particle

1. nucleic acid
2. capsid
3. envelope

Question 5

Naked Virus

Answer 5

1. stable
2. resistant to sewage and GI condts.
3. spread easily
4. released after lysis of infected cell
5. Ab imp. for immunoprotection

what is the role of ABs in immunoprotection?

Question 6

Enveloped Virus

Answer 6

1. susceptible to cold, detergents, drying, heat, GI
2. spreads in large droplets, secretions
3. organ transplants and blood transfusions
4. ABs and cell mediated- often the AB response is not enough and you need the cell mediated response as well.

they require closer contact in general.

Question 7

Capsid Assembly

Answer 7

individual protein peices assemble into subunits

Subunits->protomers->capsomeres->pro-capsid (no genome) or capsid (around genome)

Question 8

Viral Shapes

Answer 8

need electron microscope
1. helical
2. polyhedral
3. spherical

Question 9

capsid vs. procapsid

Answer 9

An empty shell made first (pro-capsid) – filled by genome later.

Question 10

Spikes

Answer 10

Spikes-glycoprotein projections through envelop help in adherence.