Topic 2C - Year 1 - Cells and the Immune System - Antigenic Variation

Question 1

What is antigenic variation?

Answer 1

Antigenic variation is when pathogens change the antigens on their cell surface slightly. this different antigens on the cell surface of the pathogen occur due to changes in the genes of the pathogen.

Question 2

Explain the consequences of antigenic variation

Answer 2

Antigenic variation means that immunity is hard to maintain as the antigens are constantly varying. The variation of the antigens mean that the B and T memory cells don’t recognise the pathogen and thus a primary response is initiated rather than a secondary response which means the body takes longer to respond.

Question 3

Which two pathogens are known to show antigenic variation?

Answer 3

HIV

Influenza