CAIE A Level Biology 9700 · Immunity
Describe the sequence of events that occur during a primary immune response to a bacterial infection entering through a wound. In your description, explain the roles of phagocytes (macrophages and neutrophils), T-lymphocytes (helper T-cells and killer T-cells), and B-lymphocytes (including plasma cells). Also explain how memory cells produced during this response contribute to long-term immunity.
7 marks, so the mark scheme is looking for about 7 separate creditworthy points. Making the same point twice in different words earns it once.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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