HIV Flashcards
What does HIV stand for?
Human Immunodeficiency Virus
What does HIV cause?
Acquired Immune Deficiency Syndrome (AIDS)
What is the structure of HIV?
1) Single stranded RNA
2) Attachment protein
3) Protein capsid
4) Lipid envelope
5) Enzyme reverse transcriptase
What does the enzyme reverse transcriptase do?
Convert RNA into DNA
Enables viral RNA to act as a template to form DNA.
What is a retrovirus?
A virus that contains RNA
What do attachment proteins bind to?
CD4 receptors on T helper cells
Explain how the HIV virus replicates [6 marks]
1) Attachment protein attaches to CF4 receptors on T helper cells
2) Capsid is released, uncoats and releases RNA into cytoplasm
3) Reverse transcriptase makes complimentary strand of DNA from viral RNA template
4) DNA is made from this and inserted into human DNA
5) Host cells enzymes used to make viral proteins from viral DNA in human DNA
6) Viral proteins assembled into new viruses, which bud off and infect other cells.
HIV is non-living and therefore cannot…
undergo cell division independently
What does AIDS stand for?
Acquired Immuno Deficiency Syndrome
Distinguish between HIV and AIDS
HIV is caused by a virus
AIDS is caused by having too few T Helper cells
Why are antibiotics ineffective against HIV?
Antibiotics do not kill viruses, only bacteria
Explain how antibiotics kill bacteria?
The murein of the cell wall of bacteria prevents the cell from bursting when water enters via osmosis.
Antibiotics inhibits enzymes that synthesise and cross linkages within the murein cell wall.