. Write the function of each of the following parts of human eye
cornea; iris; crystalline lens; ciliary muscles
Ans. Functions of the following parts of human eye:
(i) Cornea. The front part of the eye is called cornea. It is made up of a transparent substance. The light coming from objects enters the eye through cornea.
(ii) Iris. This is a flat, coloured, ring-shaped membrane behind the cornea. a hole in the middle of the iris. Iris controls the size of the pupil.
(iii) Crystalline lens. Eye lens is a convex lens which focuses the image of the on the retina.
(iv) Ciliary muscles. Ciliary muscles hold the eye lens and changes the this eye-lens while focussing.