The iris is the colored part of your eye. Muscles in your iris control your pupil. This helps you see clearly and adjust to changes in lighting.
Iris of the Eye: Definition, Anatomy & Common Conditions
Iris: Anatomy, Function, and Iris-related Conditions
Retina: Anatomy, Function & Common Conditions, retina
5,107 Iris Eye Stock Photos, High-Res Pictures, and Images - Getty Images, Iris
Eye: Definition, How does it Work, Anatomy, and Functions
Macula: Anatomy, Function & Common Conditions, retina
About the Eye National Eye Institute
Eye anatomy and physiology - how the eye and vision work
Blue Iris, Iris