Name the part of the eye:

(a) which controls the amount of light entering the eye.


(b) which converges light rays to form the image.


(c) on which image is formed.


(d) which carries the image to brain.


(e) which changes the curvature (or thickness) of eye-lens to focus objects lying at various distances.

(a) Iris controls the amount of light entering the eye by constricting and dilating the pupil in bright and dim light respectively.


(b) Lens. The lens may diverge or converge the light rays to form an image.


(c) Retina. An upside-down image is formed on the retina.


(d) Optic nerve carries the image to brain in form of electric impulses.


(e) Ciliary muscle changes the lens shape to focus objects lying at various distances.


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