CAIE A Level Biology 9700 · Immunity
A patient is infected with a new strain of influenza A virus. This is the first time the patient has encountered this strain. Several years later, the patient is exposed to the same strain again. Compare the primary and secondary immune responses to this virus, with reference to the roles of specific white blood cells.
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Compare means: Give similarities or differences between two things, and say which side each point belongs to. Write each point as a pair, for example: A is X, whereas B is Y. Two separate descriptions rarely earn the marks.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.