replication of hiv

Question 1

step 1 When the virus enters the bloodstream it infects a certain type of lymphocyte -

Answer 1

helper T cells

Question 2

Normally lymphocytes seek out and destroy pathogens that enter the body, producing antibodies that attach to pathogens and enhancing phagocytic activity

HIV avoids being recognised and destroyed by lymphocytes by

Answer 2

repeatedly changing its protein coat

Question 3

second stage

The virus uses the cell machinery of helper T-cells to multiply how

Answer 3

Viral RNA enters the cell

Viral reverse transcriptase enzymes produce a DNA copy of the viral RNA

The DNA copy is inserted into the chromosomes of the cell

Each time the cell divides it copies the viral DNA

The infected cells remain normal as the viral DNA is inactive

Question 4

third stage

At this stage, the individual is HIV positive and will have antibodies against the virus

After a period of time (possibly years) the viral DNA within the host cells becomes active and

Answer 4

It takes control of the helper T cell

More HIV particles are produced

This causes the helper T cell to die

As a result, thousands of new HIV particles are released which are able to infect other helper T cells

Question 5

forth stage Gradually the virus reduces the number of helper T cells in the immune system
till

Answer 5

B cells are no longer activated

No antibodies are produced

This decreases the body’s ability to fight off infections, eventually
leading to AIDS (Acquired immune deficiency syndrome)