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the transparent structure behind the pupil that changes shape to help focus images on the retina.
a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision
a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
middle part of the inner ear in front of the semicircular canals and behind the cochlea that contains the utricle and saccule
eye disease in which the lens becomes covered in an opaque film that affects sight, eventually causing total blindness.
increased intraocular pressure results in damage to the retina and optic nerve with loss of vision
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