Nitrogen is one of the materials that cycles through an ecosystem.
Which statement describes part of how nitrogen is cycled?
Plants take in nitrogen gas through their leaves, and animals return it to the air as they breathe.
Animals take in nitrates from the soil, and plants return nitrogen compounds to the soil as they grow.
Decomposers take in nitrates from the soil, and plants release nitrogen gas into the air at night.
Plants take in nitrates from the soil, and decomposers return nitrogen compounds to the soil.
111 exam-style questions on OCR GCSE Biology 4.1 Ecosystems, covering 4.1.1 Cycling of materials in ecosystems, 4.1.2 Microorganisms in cycling materials, 4.1.3 The carbon and water cycles, 4.1.4 Factors affecting decomposition, 4.1.5 Levels of organisation in an ecosystem, 4.1.6 Abiotic and biotic factors affecting communities, 4.1.7 Interdependence and competition, 4.1.8 Trophic levels, 4.1.9 Pyramids of biomass, and 4.1.10 Efficiency of biomass transfers. Each one has a worked solution and a mark scheme showing where the marks go.