Microbiology Part 3 (2.3)

Question 1

What do viruses do and what are they composed of?

Answer 1

• composed of protein & nucleic acid
• lack metabolism
• replicate only in host cells

Question 2

What do viroids do and what are they composed of?

Answer 2

• non - translated ssRNAs

- lack protein (infect plants)

Question 3

What do satellites do and what are they composed of?

Answer 3

• subviral infectious agents

- composed of nucleic acid & protein that require a helper virus to replicate

Question 4

What do prions do and what are they composed of?

Answer 4

• infectious proteins

- cause mad cow disease, scrapie and CJD

Question 5

What are viruses and what do they entail?

Answer 5

• particles (virions)
• genome (DNA/RNA) in a protein coat
• have an envelope
• multiply only in living cells - causing disease
• not living - no metabolism
• no growth - assembled from constituent parts
• virus- specified proteins made using host ribosomes

Question 6

Give some examples of viruses.

Answer 6

• Norovirus
• SARS-coV
• Ebola
• Mimivirus

Question 7

What are the steps of assembly for a virus?

Answer 7

• entry & uncoating
• replication
• transcription & manufacture of capsid proteins
• self - assembly of new virus particle = their exit from the cell

Question 8

What are the steps for the replication of the SARS-CoV-2 cycle?

Answer 8

• Attachment
• Uncoating
• Production of viral components
• Assembly
• Release