Anatomy of the Eye
Structure

Conjunctiva
Cornea
Choroid
Iris
Lens
Anterior Ocular Chamber
Posterior Ocular Chamber
Optic Nerve
Retina
Iris

The iris acts like a shutter. The tissue is sponge-like and embossed. The pupil is the central aperture of the iris. Change in pupillary size occurs as the iris slides over the front of the lens. The colour of the iris determines the colour of the eye. Someone with blue irises is said to have blue eyes.