HIV

Question 1

Reverse transcriptase

Answer 1

A group of viruses (retroviruses) contain reverse transcriptase
It is used to turn viral RNA into DNA so it can be transcribed by host cell into proteins

Question 2

HIV

Answer 2

HIV cnt replicate itself as it has no ribosomes and no DNA so it inserts its genetic material to instruct host cells to produce the components required to make new HIV

Question 3

Which cells does HIV target

Answer 3

Helper T cells due to complementary pairing of attachment proteins with CD4 receptor

Question 4

Describe the replication of HIV in a host cell

Answer 4

1. HIV enters blood stream
2. HIVs glycoprotein binds to CD4 protein on immune cells e.g. helper T cells
3. Capsid fuses with cell membrane
4. RNA and enzymes from HIV enter T helper cells
5. Reverse transcriptase converts RNA to DNA which is made of viral RNA
6. DNA inserted into DNA of the host cell
7. Viral DNA transcribed and translated into ribosomes in T cell to make viral proteins
8. Helper T host cells make new HIV particles
9. Particles break away from helper T cells wrapped in a piece of cell membrane, forming HIVs lipid envelope

Question 5

AIDS

Answer 5

without helper T cells, B cells and cytotoxic T cells arent activated
An immune response doesnt occur
Patients are susceptible to other infections and cancer

Question 6

What are the 3 HIV drugs

Answer 6

Fusion inhibitors
Reverse transcriptase inhibitors
Protease inhibitors

Question 7

What do fusion inhibitors do

Answer 7

Blocks the fusion of HIV to host cell

Question 8

What do reverse transcriptase inhibitors do

Answer 8

Stops viral RNA from being copied to DNA for protein synthesis

Question 9

What do protease inhibitors do

Answer 9

Inhibit proteases used in synthesis of viral proteins