Lecture 2

Question 1

What is a virus?

Answer 1

• genomes consist of nucleic acid
• replicate within cells using the cells synthetic machinery
• causes synthesis viral elements transferred from one cell to another
• very small in size

Question 2

Name three characteristics that make viruses relatively unique when compared to other organisms:

Answer 2

• very simple by nature. Able to be crystallised and yet still able to function
• Viruses either contain DNA or RNA but will never contain both
• Unique in that they will always require a living host to be able to replicate

Question 3

What are the three main layers of a virus? inside to out

Answer 3

a nucleic acid genome (RNA or DNA)
enclosed within a protein coat (or capsid)
within an envelope (modified from the host cell membrane)

Question 4

Describe the basic anatomy of parvovirus:

Answer 4

• Non-enveloped
• Isometric capsid display
• Linear DNA genome
• E.g. adenoviruses

Question 5

Describe the basic anatomy of paramyxovirus:

Answer 5

• Enveloped
• Helical capsid symmetry
• ss RNA genome
• E.g. herpesvirus

Question 6

Describe the basic anatomy of poxvirus:

Answer 6

• Enveloped
• Complex morphology
• Linear ds DNA genome
• Due to the very complex nature of these viruses they are the only DNA viruses that replicate entirely within the cell metabolism