CAIE A Level Biology 9700 · Immunity
A patient is infected with a newly discovered virus. Describe and explain the distinct roles of T-helper cells and T-killer cells during the primary immune response to this viral infection. Your answer should include how each cell type is activated and its specific function in eliminating the virus.
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.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
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