A tree dies and falls onto the floor of a forest. After 20 years the wood of the fallen tree has completely disappeared.
Explain how the carbon in the wood of the fallen tree is returned to the atmosphere.
Explain how the mineral ions in the fallen tree can end up in the leaves of a young tree growing nearby.
40 exam-style questions on AQA GCSE Biology 7.2 Organisation of an ecosystem, covering 7.2.1 Levels of organisation, 7.2.2 How materials are cycled, 7.2.3 Decomposition, and 7.2.4 Impact of environmental change (HT only). Each one has a worked solution and a mark scheme showing where the marks go.