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Read the assertion and reson carefully t...

Read the assertion and reson carefully to mark the correct option out of the options given below:
Assertion : The eye is said to have power of accomodation .
Reason : Ciliary muscles alters the shape of the lens for near or far vision during accomodation .

A

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

B

If both the assertion and the reason are true but the reason is a not correct explanation of the assertion

C

If the assertion is true but the reason is false

D

If both the assertion and reason are false

Text Solution

Verified by Experts

The correct Answer is:
B

The choriod is the middle layer of eyeball which is connected in front to a thick structure called ciliary body Thread like suspensory ligamnets extend from the ciliary body and get attached to a biconvex, transparent elastic Lens. For proper vision, light rays from a visula object must be focussed sharply and precisely on the retina In the resting eye, the ciliary muscles remain relaxed, keeping the suspensory ligaments stouly strethced which flattens the elastic lens to reduce its curvature. The lens in this resting eye focusses parallel rays from distance objects (more than 6 m away) on the retina. But to increase the power of the lens for focussing divergent rays form near object on the retina, a reflex called accomodation is needed. the eye has got the properly to form images of both near convexity of the lens. This is known as the power of accomodation.
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