The part of the eye that uses muscle tissue for opening and closing is the iris. The iris is responsible for controlling the size of the pupil, which regulates the amount of light that enters the eye. The muscles in the iris, known as the iris sphincter muscle and the iris dilator muscle, contract and relax to adjust the size of the pupil.
The part of the eye that uses muscle tissue for opening and closing is the iris. The iris is the colored part of the eye surrounding the pupil. It contains a ring of muscles called the sphincter and dilator muscles. These muscles control the size of the pupil, allowing it to constrict (become smaller) or dilate (become larger) in response to light conditions and other factors.
The part of the eye that uses muscle tissue for opening and closing is the iris. The iris is the colored part of the eye and it contains muscles that control the size of the pupil, which is the hole in the center of the iris. The muscle in the iris is called the sphincter muscle. When this muscle contracts, it makes the pupil smaller, restricting the amount of light entering the eye. When the sphincter muscle relaxes, the pupil becomes larger, allowing more light to enter the eye. This opening and closing of the iris helps to regulate the amount of light reaching the retina at the back of the eye, ensuring optimal vision in different lighting conditions.
