Eyeball Functions

Extraocular muscles

Eyeball movement

Sclera

protects eye and is site of attachment for extra ocular muscles

Cornea

bends light as it enters the eye

Iris

contains pigment for eye color and regulates size of pupil

Pupil

aperture (hole) that allows light into eye

Choroid

pigmented vascular layer which absorbs excess light and supplies oxygen to the retina

Retina

site of photo receptors (rods and cones)

Fovea Centralis

region of most condensed cones

Lens

bends and focuses light onto retina

Optic Disc

continuation of retina, conveys visual info to occipital lobe

Anterior & Posterior Cavities

The posterior cavity contains vitreous humor which provides internal support to eye and pushes retina firmly to the sclera. The anterior cavity is formed by the anterior chamber (from cornea to iris) and the posterior chamber (from iris to posterior cavity, including lens). These contain aqueous humor which delivers oxygen to cornea and lens).