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GCSE AQA Higher Biology · Topic 8 of 8
Key ideas – GCSE AQA Higher Biology revision notes
Choose a subtopic. Key ideas covers Key ideas in GCSE AQA Higher Biology. 3 lessons in 1 subtopic.
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3 lessons, grouped by subtopic.
Key ideas
- Structure, Function and Organisation in Living Things: Explore how molecular structure relates to function, understand cells as fundamental units of life, and examine how cells form tissues, organs and organ systems to carry out life processes effectively.
- Ecosystems and Energy Flow: Investigate how organisms form populations, communities and ecosystems, explore interdependence and adaptations, and understand the role of photosynthesis and cellular respiration in energy transfer through living systems.
- Genetics, Evolution and Chemical Cycles: Examine how chemical cycling maintains ecosystems, understand how genome and environment influence organism characteristics, and explore how natural selection drives evolution and biodiversity.
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Frequently asked questions
What is Key ideas?
Key ideas covers Key ideas in GCSE AQA Higher 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.