CAIE A Level Biology 9700 · Homeostasis

Homeostasis: outline question

Outline7 marksChallenge

During a hot day, a mammal loses water through sweating and panting, leading to a decrease in blood water potential. Outline the sequence of events that occur to restore blood water potential to normal, starting with the detection of the change by osmoreceptors.

How this question is marked

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.

Outline means: Give the main points briefly. Less detail than describe, but every key step has to be there. One short line per step, in order. The marks are for coverage, not depth.

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