If you are experiencing a medical emergency please dial 911 immediately
The pupil is the black area in the center of the iris, the colored part of the eye. The iris controls the size of the pupil in response to light outside the eye so that the proper amount of light is let into the eye.
Light passes through the pupil to the back of the eye, where an image is formed of what the eye is looking at.
Last Revised: May 29, 2013
Author: Healthwise Staff
Medical Review: Kathleen Romito, MD - Family Medicine & Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology
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