How to Revise IGCSE Biology Topic 14: Coordination and Homeostasis
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Reviewer participation may vary by guide. Checked against Cambridge IGCSE Biology 0610 (2026–2028); last reviewed August 2026.
Key point
Master the reflex arc pathway. Label the eye and explain accommodation. Know insulin/glucagon negative feedback for blood glucose. Distinguish Type 1 and Type 2 diabetes.
Topic 14 is one of the largest topics and covers two systems: the nervous system (neurones, reflex arcs, the eye) and the endocrine system (hormones, blood glucose regulation, negative feedback). Both are heavily examined.
Priority 1: Reflex arc
Stimulus → receptor → sensory neurone → relay neurone (in CNS) → motor neurone → effector → response. Know the function of each component and the role of synapses (chemical transmission via neurotransmitters across the gap).
Priority 2: Eye structure
Know the function of each part: cornea (refracts light), iris (controls pupil size), lens (focuses light on retina), retina (contains light-sensitive receptor cells), optic nerve (carries impulses to brain). For Extended: accommodation: how the ciliary muscles and suspensory ligaments adjust lens shape for near/far vision.
Priority 3: Blood glucose regulation
Insulin (from beta cells): lowers blood glucose by promoting glucose uptake and glycogen storage. Glucagon (from alpha cells): raises blood glucose by converting glycogen to glucose. Negative feedback maintains homeostasis. Know Type 1 vs Type 2 diabetes differences.
Frequently asked questions
What is the most commonly tested part of Topic 14?
The reflex arc and blood glucose regulation (insulin/glucagon negative feedback). Both appear almost every year.
Put the guide into practice
Questions and practical resources
Use a fresh question to check whether the idea can be applied without prompts.