Question

(a) Write the function of each of the following parts of human eye :
cornea, iris, crystalline lens, ciliary muscles
(b) Millions of people of the developing countries of the world are suffering from corneal blindness. These persons can be cured by replacing the defective cornea with the cornea of a donated eye. A charitable socity of your city has organised a compaign in your neighbourhood in order to create awareness about this fact. If you are asked to participate in this mission how would you contribute in this noble cause ?
(i) State the objective of organising such compaigns.
(ii) List two arguments which you would give to motivate the people to donate their eyes after death.
(iii) List two values which are developed in the persons who actively participate and contribute in such programmes.

Answer 1

(a) 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 subject enters the eye through cornea.
(ii) Iris. This is a flat, coloured , ring-shaped membrane behind the cornea. Pupil is 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 object on the retina.
(iv) Ciliary muscles. Ciliary muscles hold the eye lens and changes the thickness of eye-lens while focussing .
(b) (i) Objective of such campaigns. To make people aware of corneal blindness and make them realise their duties towards the society by taking pledge for eye donation.
(ii) `*` One pair of eyes can give eyesight to two corneal blind persons (each getting one eye), and make them see this beautiful world.
`*` Our eyes can live even after our death. People belonging to all age groups , even people with medical conditions like cataract, diabetes , hypertension can donate their eyes.
(iii) Values developed in persons who actively participate in such programmes:
`*` Concern for others and social welfare
`*` Responsible behaviour and awareness.