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Lens in the Eye

A clear disk that focuses light, as in a camera or microscope. In the eye, the lens is a clear, curved structure at the front of the eye behind the pupil. It focuses light rays that enter the eye through the pupil, making an image on the retina (light-sensitive layers of nerve tissue at the back of the eye). NIH - National Cancer Institute

Terms to know

Choroid
A thin layer of tissue that is part of the middle layer of the wall of the eye, between the sclera (white outer layer of the eye) and the retina (the inner layer of nerve tissue at the back of the eye). The choroid is filled with blood vessels that bring oxygen and nutrients to the eye.
Ciliary Body
A part of the middle layer of the wall of the eye. The ciliary body includes the ring-shaped muscle that changes the size of the pupil and the shape of the lens when the eye focuses. It also makes the fluid that fills the eye.
Cornea
The transparent part of the eye that covers the iris and the pupil and allows light to enter the inside.
Eye
Eyes are the organs of vision. They detect light and convert it.
Eyelid
An eyelid is a thin fold of skin that covers and protects the eye.
Iris
The colored tissue at the front of the eye that contains the pupil in the center. The iris helps control the size of the pupil to let more or less light into the eye.
Optic Nerve
A bundle of more than 1 million nerve fibers that carries visual messages from the retina to the brain.
Pupil
The opening at the center of the iris. The iris adjusts the size of the pupil and controls the amount of light that can enter the eye.
Retina
The light-sensitive tissue lining at the back of the eye. The retina converts light into electrical impulses that are sent to the brain through the optic nerve.
Sclera (White of the Eye)
The white layer of the eye that covers most of the outside of the eyeball.
Vitreous Humor (Aqueous Humor)
The clear jelly-like substance that fills the inside of the eyeball. As a person ages, the vitreous humor becomes more liquid.

Terms to know

Choroid
A thin layer of tissue that is part of the middle layer of the wall of the eye, between the sclera (white out...
Ciliary Body
A part of the middle layer of the wall of the eye. The ciliary body includes the ring-shaped muscle that chan...
Cornea
The transparent part of the eye that covers the iris and the pupil and allows light to enter the inside....
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