Question

Class X Sciences
[papers from previous years]

(a) List the parts of the human eye that control the amount of
light entering into it. Explain how they perform this function.
(b) Write the function of retina in human eye.
(c) Do you know that the corneal-impairment can be cured by
replacing the defective cornea with the cornea of the donated eye?
How and why should we organise groups to motivate the community
members to donate their eyes after death?

Answer 1

a) Pupil control the amount of light entering the eye.The pupil changes size to adjust for amount of light available.
b) Retina is the nerve layer lining back of the eye. The retina senses light and convert it into neural signals that are sent to the brain.
c) Cornea transplantation involves replacing the cornea. In this process only cornea is replaced..Eye donation should be encouraged because it's just like a priceless gift which one person give to other and also this is how even after death he or she is alive..

Answer 2

a} pupil controls the amount of light entering by ajusting focal length.                                                                    
b} Retina is light sensitive part which forms image.                                                                  
c} eye is precious orgon  by which we can visualise objects& if we die we should donate to the required person so that he or she can able to see this colourful world.