Parts of the Eye

cornea

tough protective layer at the front of the eye; covering the pupil and iris; refracts light to the lens;

eyelid

the skin covering the eye - it limits the light entering the eye and spreads tears

iris

the colored part of the eye - it controls the amount of light entering the pupil

lens

the clear curved part of the eye that bends the light rays - it helps to focus light on the retina

optic nerve

the bundle of over one million nerve fibers going from the back of the eye - it carries the visual messages from the retina to the brain

pupil

the opening at the center of the iris - the iris adjusts the size of this opening to control the amount of light that enters.

retina

the layer of at the back of the eye containing light receptor cells; has cells to detect colour;

sclera

the tough, white outer coat of the eye (S)

aqueous humor

liguid in the eye generated from blood plasma

vitreous humor

Fills the space between lens and retina

circular

muscles that contract in bright light to reduce the size of the pupil

radial

muscles that contract in dim light to increase the size of the pupil

ciliary muscle (body)

ring of muscle around the lens that contracts to allow the eye to take a thick shape

suspensory ligaments

can slacken to allow the lens to take a thick shape, or tighten to cause the lens to take a thin shape