The eye has two primary functions:

1) To focus light rays on the retina and
2) To create an image to send to the brain.

• Cornea -- the clear front window of the eye. The cornea transmits and focuses light into the eye.
• Iris -- the colored part of the eye. The iris helps regulate the amount of light that enters the eye.
• Pupil -- the dark center in the middle of the iris. The pupil determines how much light is let into the eye. It changes sizes to accommodate for the amount of light that is available.
• Lens -- the transparent structure inside the eye that focuses light rays onto the retina.
• Retina -- the nerve layer that lines the back of the eye. The retina senses light and creates impulses that are sent through the optic nerve to the brain.
• Macula -- a small area in the retina that contains special light-sensitive cells. The macula allows us to see fine details clearly.
• Optic Nerve -- the nerve that connects the eye to the brain. The optic nerve carries the impulses formed by the retina to the brain, which interprets them as images.
• Vitreous -- the clear, jelly-like substance that fills the middle of the eye.