ANATOMY

Detailed explanation-1: -The eyes automatically adjust the size of pupil according to the intensity of light. If the amount of light is very high, the iris contracts the pupil and reduces the amount of light entering the eye. If the amount of light around us is small, the iris expand the pupil so that more light can enter the eye.

Detailed explanation-2: -Pupil: The pupil is the opening at the center of the iris through which light passes. The iris adjusts the size of the pupil to control the amount of light that enters the eye.

Detailed explanation-3: -The iris and the pupil control how much light to let into the back of the eye. When it is very dark, our pupils are very large, letting in more light. The lens of a camera is able to focus on objects far away and up close with the help of mirrors and other mechanical devices.

Detailed explanation-4: -The size of the pupil is controlled by Iris. Iris contains a group of two smooth muscles attached at the corner of the pupil. They stretch when there is less light and shrink when it is too bright.