Science (086) — AI-generated practice question

(i) Cornea: The cornea is the transparent membrane on the front of the eyeball where most refraction of light occurs. If absent or damaged, light cannot be properly refracted into the eye, causing severely blurred or complete loss of vision.

(ii) Iris: The iris is a dark muscular diaphragm that controls the size of the pupil, regulating the amount of light entering the eye. If damaged, the eye cannot adjust to varying light intensities, causing discomfort or poor vision in bright/dim conditions.

(iii) Retina: The retina is a delicate membrane containing light-sensitive cells that generate electrical signals sent to the brain via optic nerves. If damaged, images cannot be detected or transmitted to the brain, leading to loss of vision.

Source: Chapter 10, Section 10.1 – The Human Eye

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• Each part requires a function + consequence of damage — examiners award marks for both parts together.
• Use textbook terminology: "muscular diaphragm" (iris), "transparent membrane / most refraction" (cornea), "light-sensitive cells / electrical signals" (retina).
• Do not confuse pupil (opening) with iris (the muscle controlling it) — a common error.
• Keep each point to 2–3 lines; one mark per part.