Iris and Pupil

Overview

This is an eye showing the iris, a circular structure that gives the eye colour, and the pupil which is the black hole in the middle of the iris.
The iris and pupil

The iris is the structure that gives the eye colour. The pupil is the black hole in the middle of the iris. The iris determines the amount of light going into the eye by controlling the size of the pupil.

If we see a bright light, the iris contracts and the pupil becomes smaller. The opposite occurs if there is less light (such as in a dark room).

This is an eye showing the iris, a circular structure that gives the eye colour, and the pupil which is the black hole in the middle of the iris.
The pupil constricts (becomes small) with light, dilates (becomes big) in dark
Updated on July 23, 2020
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