Levels of organisation in ecosystems (organism, population, community, ecosystem). Biotic and abiotic factors. Predator-prey relationships. Cycles (carbon, water, nitrogen). Biodiversity and human impact (climate change, deforestation, pollution). Sustainability.

Tested by

Not in Edexcel IGCSE Human Biology. A learner taking only Human Biology will not encounter formal ecological content as part of their qualification. If ecological literacy is important for an individual learner’s interests or post-16 destination, Combined Science is the appropriate science pathway.

This is a clear architectural diagnostic the spine-and-overlay model surfaces: the same canonical strand is tested by some overlays but not others, and the choice of overlay determines what content the learner formally encounters.

Precursor