RNA Viruses

Question 1

What is an RNA virus?

Answer 1

Agents that store genetic infromation in RNA molecules

Question 2

How are RNA viruses categorized?

Answer 2

RNA viruses are categorized by several factors

• Their genomic structure
• Presence of an envelope
• Size and shape of their capsid

Question 3

Types of RNA viruses

Answer 3

1- Rpositive songle0stranded RNA (+ssRNA)

2) Retroviruses (+ssRNA viruses that convert their genome to DNA)
3) Negative single-stranded RNA (-ssRNA)
4) Double-stranded RNA (dsRNA)

Question 4

Function of Positive and negative RNA

Answer 4

• Positive RNA can be used by a ribosome to translate protein
• Negative RNA transcribed as mRNA to be processed by a ribosome

Question 5

Examples of synthesis of RNA viruses of animals

Answer 5

1) Positive ssRNA viruses: Poliovirus
2) Negative ssRNA viruses: Rabies, flu
3) dsRNA viruses: Rotaviruses
4) Retroviruses: HIV
- Does not use their genomes (+ssRNA) as mRNA
- Use DNA intermediary transcribed by reverse transcriptasae as a template to generate +RNA moleculesw used to produce viral genomes and as mRNA