The iris is the colored part of your eye.
It is the muscular curtain that sits near the front between the cornea and the lens.
The iris constricts when its bright out and opens up in lower light conditions.
Illustration by Julie Bang for Verywell Health
This is called the pupillary light reflex.
The iris sits in theuvealtract, which is the eye’s middle layer.
The iris splits the space between the cornea and lens into anterior and posterior chambers.
Both chambers are filled with aqueous humor.
Eye Color
Your eye color is determined by a combination of different pigments and saturation levels.
Dilation and constriction of the pupil can also be influenced by physiological states, such as arousal and excitement.
Disorders that affect the iris can occur due to genetic abnormalities or other conditions.
There are several tests your healthcare provider can use to assess eye health and diagnose eye conditions.
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