IGCSE Biology glossary
Retina
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 light-sensitive layer at the back of the eye containing photoreceptor cells (rods and cones) that detect light and convert it into nerve impulses. These impulses are sent to the brain via the optic nerve for interpretation as images.
What to include in an exam answer
The retina contains light receptors. Rods detect dim light (black and white vision) and cones detect colour. The fovea is the area of the retina with the most cones for sharp colour vision.
Example in context
State the function of the retina (1 mark): The retina contains light-sensitive cells (receptors) that detect light and convert it into nerve impulses sent to the brain.
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