What does a iris do in eye?

Answer 1

The, Iris expands and contracts to regulate the amount of light that enters the eye.
The colored part of the eye is called the iris. It controls light levels inside the eye similar to the aperture on a camera. The round opening in the center of the iris is called the pupil. The iris is embedded with tiny muscles that dilate (widen) and constrict (narrow) the pupil size.

The sphincter muscle lies around the very edge of the pupil. In bright light, the sphincter contracts, causing the pupil to constrict. The dilator muscle runs radially through the iris, like spokes on a wheel. This muscle dilates the eye in dim lighting.

The iris is flat and divides the front of the eye (anterior chamber) from the back of the eye (posterior chamber). Its color comes from microscopic pigment cells called melanin. The color, texture, and patterns of each person's iris are as unique as a fingerprint.

Answer 2

The iris is the colored part of the eye and it is responsible for regulating how much light is allowed to pass to the back of the eye. So it serves as a protective mechanism to prevent too much light in bright conditions and allows more light in dim/dark conditions.

Answer 3

The iris is the colored ring shaped membrane behind the cornea of you eye, with the pupil in the middle of it. [simple version- it is the colored bit you can see other than the white of your eye and the pupil]

Answer 4

The iris is the colored part of your eye. Iris was the name of a Greek goddess of the rainbow.

Answer 5

The iris regulates the size of the pupil, increasing or decreasing the amount of light that enters the eye. The iris contains muscles that expand and contract.

Answer 6

then clour full part of the eye