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Tough, white outer layer of the eye

choroid coat

middle layer of the eye; contains blood vessels


The light sensitive layer of the eye which is composed of receptors (rods and cones).

aqueous humor

anterior cavity of the eye filled with clear, watery fluid

vitreous humor

the clear colorless transparent jelly that fills the posterior chamber of the eyeball


a condition in which nearby objects are seen more clearly than distant objects


condition in which vision for distant objects is better than for near objects


rod-shaped receptor in the retina of the eye that is sensitive to dim light but not color


Receptor cells in the retina that are sensitive to bright light and produce color vision.


visible part of the outer ear. It collects sound and directs it into the auditory canal


the membrane that seperates the outer ear from the middle ear and that vibrates when sound waves strike it (tympanic membrane)


the bone attached to the eardrum


the bone between the hammer and the stirrup


a tiny U shaped bone that passes vibrations from the anvil to the cochlea

oval window

membrane that covers opening between middle ear and inner ear


a coiled tube that is found in the inner ear and that is essential to hearing

semicircular canal

3 loops of fluid filled tubes that that are attached to to the cochlea; maintains equilibrium

olfactory cells

sensitive nerve cells in nasal passages.

eustachian tubes

tube connecting ear to throat; helps to equalize pressure

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