Foundation & Higher

Decomposition and decay GCSE questions

Cover the answers and try these Decomposition and decay checks first. The full quiz in the app includes hints.

How to use these

Write your answer, then check. If you miss one, open the Decomposition and decay lesson before you retry.

Practice questions

Cover the answers and have a go first. Worked solutions are underneath.

Question 1 [1 mark]

The main decomposers are

Question 2 [1 mark]

Decomposers return carbon to the air mainly as

Question 3 [1 mark]

Decay is fastest when conditions are

Question 4 [1 mark]

Turning a compost heap adds

Common mistakes

Answers and working

Q1. bacteria and fungi
Q2. carbon dioxide from respiration
Q3. warm, moist and aerobic
Q4. oxygen for aerobic microbes

Frequently asked questions

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