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What is 1 + 3?
the transparent outer covering of the eye
colored part that controls amount of light in eye
opening in the center of the iris where light rays enter
transparent structure behind the pupil that bends and focuses light rays on the retina
inner surface of eye covered by cones and rods
only able to see close objects for image forms before the retina. needs concave lens
only able to see far objects for image forms behind the retina. needs convex lens