19) Accomodation describes the focusing of light on the retina by changing 19) A) the shape of the lens. B) the shape of the cornea. C) distance of the retina from the lens. D) pupillary diameter.

A. The shape of the lens.

Explanation:

The process by which eyes of vertebrates changes the optical power of lens in order to get a clear image on the retina of eye for nearer as well as far objects is known as Accommodation. As we need to see both near and far objects, our eye adjusts itself so that we see the clear images. This process is accomplished by changing the shape of the lens present in eye. Ciliary muscles which hold the lens help in changing its shape. Due to change in shape the focal length of the lens changes and thus the final image by the lens is always formed at the retina, either the object is near or far.

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