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Ch 4 Section 3&4

Science Key Terms

index of refraction a measure of how much a ray of light bends when it enters that material
mirage an image of a distant objet caused by refraction of light
lens a curved piece of glass or other transparent material that is used to reflect light
convex lens thicker in the center than at the edges
concave lens thinner in the center than at the edges
cornea light enters the eye through the transparent front surface
pupil an opening through which light enters the inside of the eye
iris a ring of muscle that contracts and expands to change the size of the pupil
retina a layer of cells that line the inside of the eyeball
rods cells that contain a pigment that responds to small amounts of light
cones cells that respond to color
optic nerve the rods and cones send signals to the brain along a short thick nerve
nearsighted a person that can see nearby things clearly but objects at a distance are blurred
farsighted a person that can see distant objects clearly, but nearby objects appear blurry
Created by: lkdickson