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Author: Nathan Lampson

This lesson will examine the structure of the eye and will identify how our brain processes visual signals.

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Developing Effective Teams

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Terms to Know
Aqueous Humor

Fluid within the eyeball that maintains pressure and transmits light.

Cone Cells

A photoreceptor that detects bright light.


A layer that covers the iris and helps to focus light into the eye.


An area of the retina where vision is the most acute.


The colored portion of the eye.


A structure in the eye that focuses light to the retina.

Optic Nerve

A nerve that sends impulses to the visual cortex in the brain where images are interpreted.


Cells that detect light found on the basement layer of the retina; includes rods and cones.


The black part of the eye through which light enters.


An area in the back of the eye that contains photoreceptors to absorb light.

Rod Cells

A photoreceptor that detects dim light.


The white of the eye that aids in protection.


The perception of light, images and movement by the eye.

Visual Cortex

The part of the brain that receives nerve impulses from the optic nerve.

Vitreous Humor

Fluid within the eyeball that supports the lens and the eyeball.