Describe the role of decomposers in the cycling of materials in an ecosystem.

Eduqas GCSE Biology — 6.2 The principle of material cycling · Describe · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

Decomposers break down dead organisms and waste material.
They release nutrients and minerals back into the soil or environment.
Plants can then take up or absorb these nutrients.
Thus the same atoms and molecules are reused, allowing materials to be recycled in the ecosystem.

Examiner tips

Use the exact terms 'decomposers', 'break down', 'release nutrients', 'recycled', 'reused'; keep each point short and clear.
Show the causal link: decomposition → nutrient release → plant uptake → recycling.

Common mistakes

Confusing decomposers with predators or producers; not mentioning nutrient release; using vague words like 'help' instead of 'recycle'.

Mark scheme (4 marks)

Decomposers break down dead organisms / waste material
Decomposers release nutrients / minerals back into the soil / environment
These nutrients / minerals can then be taken up / absorbed by plants
This allows materials to be reused / recycled, so the same atoms / molecules pass through living organisms again

Key terms in this question

decomposers · cycling of materials