Intro to Viruses

Question 1

In what two forms can viruses exist?

Answer 1

Virions and replicative forms

Question 2

What are the two types (shapes) of capsids?

Answer 2

Helical and icosahedral

Question 3

What are the three types of possible viral DNA genomes?

Answer 3

Linear DS, linear SS, circular SS

Question 4

What are the four types of possible viral RNA genomes?

Answer 4

1. Linear, + stranded
2. Linear, - stranded
3. Segmented, - stranded
4. Segmented, DS

Question 5

What are the four ways in which viruses get monocistronic eukaryotic machinery to make multiple viral proteins?

Answer 5

1. Polyprotein (single peptide is cleaved by proteases)
2. Segmented genome
3. Nested mRNA (will not be covered)
4. Differential splicing

Question 6

Which two genome types are infectious (without needing viral enzymes, proteins, etc)?

Answer 6

DS DNA and (+) RNA-AAAA