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Biology
OCR GCSE Biology A
Community level systems
Ecosystems

OCR GCSE Biology A · J247

Ecosystems

Subtopics

1
Material cycling
2
Role of microorganisms
3
Carbon and water cycles

10 of 10 subtopics have revision notes available.

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B4.1 Ecosystems Revision — OCR GCSE Biology A J247

4

Factors affecting decomposition

Levels of organisation

Abiotic and biotic factors

Interdependence and competition

Pyramids of biomass

Efficiency of biomass transfer