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GCSE AQA Higher Combined Science Biology · Topic 8 of 8
Key ideas – GCSE AQA Higher Combined Science Biology revision notes
Choose a subtopic. Key ideas covers Key ideas in GCSE AQA Higher Combined Science Biology. 3 lessons in 1 subtopic.
Revise Key ideas for GCSE AQA Higher Combined Science Biology, including Key ideas. 3 lessons across 1 subtopic.
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Key ideas
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AQA GCSE Combined Science Biology mock draft, 26–31 Oct. Draft coverage: Combined Science Biology Paper 1 (Higher tier). Reviewed for an original-practice sitting; check student availability before registering. Marking and results will follow later, after separate approval. Eligible new accounts receive a five-day Pro trial when signup email verification completes. Previous trials keep their original expiry. After expiry, new papers need Pro unless you have an explicitly confirmed free sitting offer for this event. That offer adds no Pro time or AI learning. Saved attempts and released results remain readable. No card or automatic charge.
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What is Key ideas?
Key ideas covers Key ideas in GCSE AQA Higher Combined Science Biology. 3 lessons in 1 subtopic.
How is a nerve cell adapted to its function?
A nerve cell can be over a metre long, with branching dendrites and a long axon. The Structure, Function and Organisation in Living Things notes cover this in full.
How much DNA do humans share with bananas?
Humans share about 50% of their DNA with bananas, but 99% with chimpanzees. The Genetics, Evolution and Chemical Cycles notes cover this in full.
How are Arctic foxes adapted?
Arctic foxes have thick white fur, a structural adaptation, and hunt at night, a behavioural adaptation. The Ecosystems and Energy Flow notes cover this in full.
How are alveoli adapted for gas exchange?
Alveoli are tiny spheres with walls just one cell thick, surrounded by dense networks of capillaries, giving the lungs a surface area of about 70 square metres. The Structure, Function and Organisation in Living Things notes cover this in full.
What is the carbon cycle?
The carbon cycle is the continuous movement of carbon atoms through the atmosphere, living organisms, oceans and rocks. The Genetics, Evolution and Chemical Cycles notes cover this in full.
What is the evidence for evolution?
Evidence for evolution comes from fossils showing a progression from simple to complex life, DNA showing that organisms with similar DNA are more closely related, similar bone structures suggesting common ancestry, and direct observation, such as Galápagos finch beak size increasing within a few generations during droughts. The Genetics, Evolution and Chemical Cycles notes cover this in full.
How does the nitrogen cycle start?
The nitrogen cycle starts when nitrogen gas from the atmosphere is 'fixed' by bacteria into compounds plants can use. The Genetics, Evolution and Chemical Cycles notes cover this in full.
What is mutualism?
Mutualism is a relationship where two species both depend on each other. The Ecosystems and Energy Flow notes cover this in full.