Antiviral (Uncompleted)

Question 1

Size of virus

Answer 1

20-30nm

Question 2

Difference between virus and virion

Answer 2

Virion is the free-living virus particle outside the host cell

Question 3

Classification of viruses

Answer 3

1. DNA viruses - less deadlier. E.g Adenovirus, HPV, pox virus, papilomavirus
2. RNA virus- the rest.
   E.g Arenavirus(Lassa fever, meningitis), Paramyxovirus(measles,mumps,RTI), Retroviruses, influenza

Question 4

Viral replication types

Answer 4

DNA virus- viral DNA enters host cell where transcription into mRNA occurs catalyzed by RNA polymerase

RNA virus- enzymes within virus synthesize mRNA from viral RNA template.

Retroviruses - contain reverse transcriptase enzyme which makes DNA copy of viral RNA

Question 5

Host defences against virus

Answer 5

1. Intact skin
2. Innate and adaptive immune response
3. NK cells
4. gene silencing

Question 6

Viral ways of avoiding host defences

Answer 6

1. Subversion of immune response; mimic extracellular ligand binding domains of cytokines
2. Evasion of immune detection and attack by T-cells;

a. Inhibition of generation of antigen
b. Interference with apoptic pathway
c. Adopting the baby turkey ploy