Parts of The Eye!
Cornea: Bulge in front of eye
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Protects eye
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First part of eye to focus light on retina
Pupil: Black dot at center of eye.
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Opening in the iris
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With iris, controls amount of light that gets into eye
Iris: Colored ring in center of eye
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Stretches and shrinks pupil to control amount of light
Lens: Clear structure in eye
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Focuses light on retina by changing shape
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Becomes rounder to focus on nearby things
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Stretches flat to focus on faraway things
Ciliary Muscles: Muscles that stretch out or squeeze lens to focus it.
Vitreous Humor: Liquid in eye - Keeps eye from collapsing
Retina: Area on back of eye -
Contains photoreceptors - neurons that respond to light.
There are two kinds of photoreceptors:
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Rods: on outer edge of retina
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Work when there's only a little light
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Only see black and white
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Cones: Nearer center of retina
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Work only in bright light
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See color
Fovea: Center of retina, where most cones are
Blind spot - place in back of eye where all photoreceptors weave together
to make optic nerve. No rods or cones in blind spot.