Immunity and the evolutionary raceEdexcel International A Level Biology: Flashcards
What these 13 flashcards ask
- What is active immunity?
- What is passive immunity?
- Give an example of natural active immunity.
- Give an example of artificial active immunity.
- Give two examples of natural passive immunity.
- Give an example of artificial passive immunity.
- Why is passive immunity short-lived?
- What is antigenic variation?
- How does a capsule protect a bacterium?
- How does M. tuberculosis survive in macrophages?
- How does HIV weaken the immune system?
- What is the evolutionary race?
- Why must flu vaccines be updated regularly?
Exam questions on Immunity and the evolutionary race
- A baby is breast-fed and receives antibodies from her mother in the milk. At eight weeks old she is also given her first dose of a vaccine against whooping cough.Distinguish between active and passive immunity.2 marks
- A traveller is bitten by a dog in a region where rabies occurs. At the clinic he is immediately injected with ready-made rabies antibodies, and is then given a course of rabies vaccine over the following weeks.Explain why the injected antibodies give the traveller only short-term protection.2 marks
- Influenza viruses accumulate mutations in the genes for their surface antigens, so a new strain appears every few years. Each year a new influenza vaccine has to be produced against the strains most likely to be circulating.Explain why a person who has recovered from influenza one year may become ill again when a new strain appears.3 marks
Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).