AQA GCSE Biology contents

Unit 5 · Homeostasis & Response

The Brain & The Eye [Biology only]

3 min read · part of the full Exam Guide

The brain

  • The brain controls complex behaviour. It is made of billions of interconnected neurones and has regions with different functions
Region Function
Cerebral cortex (the outer, wrinkled part) consciousness, intelligence, memory, language
Cerebellum (at the back, underneath) coordination of muscles, balance
Medulla (at the top of the spinal cord) unconscious activities: heart rate, breathing

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regions of the brainspinal cordcerebral cortexthe folded outer layer — consciousness,intelligence, memory and languagecerebellummuscle co-ordination and balancemedullathe unconscious things: heart rate andbreathing ratepituitary glandthe master gland — it releases hormonesthat control other glandsThe brain is extremely complex and delicate, it is encased in the skull, and the regions are notneatly separated — which is why investigating and treating brain disorders is so difficult.Scientists study it by looking at patients with brain damage, by stimulating parts of itelectrically, and by using MRI scans.
Side view of the brain with the cerebral cortex, cerebellum and medulla labelled and their functions written beside them

  • (HT) Neuroscientists have mapped regions to functions by studying patients with brain damage (a damaged area and a lost ability), by electrically stimulating parts of the brain and observing the effect, and by MRI scanning, which shows which areas are active during a task
  • (HT) Investigating and treating the brain is difficult because it is complex (billions of connections) and delicate: surgery risks damage, drugs may not cross into the brain, and damaged neurones do not easily repair

Full Exam Guide

The rest of this topic is in the full Exam Guide

The complete AQA GCSE Biology guide — every topic, exam checklist and common mistake — is coming soon. Until then, the first topic in every unit is free to read.

In the full topic

  • The brain
  • The eye
  • Adaptation to light
  • Accommodation
  • Eye defects
Read the free biology topics →