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Retina and Macula



Diagram of the Eye


The light-sensitive membrane in the back of the eye that converts the light upon it to electrical impulses that are processed and sent to the brain through the optic nerve.

A shallow pit in the center of the retina that is responsible for our sharpest straight ahead vision.


The central retina that contains the fovea.

Optic nerve
The nerve that carries the message of vision from the retina to the brain.

Vitreous gel
Vitreous gel (also called vitreous humor) is a thick, colorless gel (egg white) that fills the large space in the middle of the eye, behind the lens.


The colored part of the eye that consists of a muscular diaphragm surrounding the pupil and regulates the light entering the eye by expanding and contracting the pupil.

The transparent convex membrane that covers the pupil and iris of the eye

The dark circular opening at the center of the iris in the eye, where light enters the eye.

The part of the eye that focuses light to produce an image on the light-sensitive cells of the retina. It is nearly spherical and convex on both sides, and sits behind the pupil.

Illustration provided courtesy of the National Eye Institute, US National Institutes of Health

Definitions from Encarta® World English Dictionary [North American Edition] © and (P)2007 Microsoft Corporation