IGCSE Biology glossary
Accommodation
Biology editorial review is supported by the named review panel. Reviewer participation may vary by guide. Checked against Cambridge IGCSE Biology 0610 (2026–2028); last reviewed August 2026.
Definition
The process by which the eye changes the shape of the lens to focus on objects at different distances. For near objects, the lens becomes fatter; for distant objects, it becomes thinner. This is controlled by the ciliary muscles and suspensory ligaments.
What to include in an exam answer
For near objects: ciliary muscles contract, suspensory ligaments slacken, lens becomes fat (more convex). For distant objects: ciliary muscles relax, suspensory ligaments pull tight, lens becomes thin (less convex). Know both directions.
Example in context
Explain how the eye accommodates to focus on a distant object (3 marks): The ciliary muscles relax, causing the suspensory ligaments to become taut. They pull on the lens, making it thinner and less convex. This decreases refraction so that light from the distant object is focused on the retina.
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