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Question
The diagram given below represents the cross-section of the human eye:
(i) Name the parts labeled 1—12.
(ii) What is the function of the part marked ‘10’?
(iii) What would happen if part ‘5’ is damaged or cut?
Solution
(i)
1. Sclerotic
2. Choroid
3. Retina
4. Yellow spot or fovea
5. Optic nerve
6. Blindspot
7. Lens
8. Aqueous humour
9. Pupil
10. Iris
11. Vitreous humour
12. Cornea.
(ii) The function of the part marked ‘10’, the iris, is to regulate the amount of light that enters the eye so that too much light does not damage the delicate cells of the retina.
(iii) The person would not see because the sensations from the eye would not reach the brain.
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