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Biology A level Stimuli and response exam question AQA

I am stuck on this question and have researched online but I can't seem to find anything to help. Any guidance would be appreciated.

Adults lay eggs which hatch into larvae. Larvae feed and grow and eventually turn into pupae. During the pupal stage, no feeding takes place and the adult body is formed. The adults and larvae feed on plants.

Pupae that develop in late summer enter diapause, a state in which the rate of metabolism is very greatly reduced. Adults do not emerge from these pupae until the following spring. This is an adaptation to changed in food availability and abiotic conditions. Explain how a slower metabolic rate is of benefit to the insect.
(edited 4 years ago)
Reply 1
A levels are all about testing your application of knowledge rather than just your recall of knowledge.

Take it back to basics and don’t get overwhelmed by the question... What do you know about metabolism? As a general rule, the greater the mass of an organism the higher that organism’s metabolic rate is.

You won’t necessarily be taught this but insects go through a cycle called diapause which is what the question is talking about above. As conditions around that insect change; this could be, temperature, food availability, length of the days and also their life cycle - an insect will start stages of diapause to slow down their metabolism to reserve energy.

- In answer to the question, a slower metabolic rate benefits the insects because they will be able to conserve energy for longer periods of time, even when living conditions are tough. All in all, it increases the change of survival as they only come out of diapause and increase their metabolic rate when conditions are more favourable. When answering the question you may need to include abiotic factors the insect may face.

I hope this helps!
Reply 2
Original post by mushed
I am stuck on this question and have researched online but I can't seem to find anything to help. Any guidance would be appreciated.

Adults lay eggs which hatch into larvae. Larvae feed and grow and eventually turn into pupae. During the pupal stage, no feeding takes place and the adult body is formed. The adults and larvae feed on plants.

Pupae that develop in late summer enter diapause, a state in which the rate of metabolism is very greatly reduced. Adults do not emerge from these pupae until the following spring. This is an adaptation to changed in food availability and abiotic conditions. Explain how a slower metabolic rate is of benefit to the insect.


pupae survive the winter;
conserves fat/energy stores;
(reject reference to pupa feeding)
when no food/plants (for larva/adult);
temperature too cold for survival;

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