Nerves that branch off the spinal cord
Spinal nerves
Moisten the underside of your eyelids and keep the surface of the eyeball clean and moist; destroy bacteria and help prevent eye infections
Tears
A person specifically trained to examine eyes and to prescribe corrective lenses for defective vision
Optometrist
The special nerve of hearing that is first stimulated by vibrations of the liquid in the cochlea and then carries messages to the brain
Auditory nerve
The tiny middle-ear bone between the hammer and stirrup
Anvil
Screen out tiny bits of dust
Eyelashes
Sensory receptors on the surface of your tongue
The transparent covering of the iris and pupil through which light enters the eye
Cornea
Liquid-filled structures in the inner ear that help maintain balance in the body
Semicircular canals
The tiny middle-ear bone that touches the eardrum
Hammer
Help keep perspiration from running down into your eyes
Eyebrows
Close to shut out too great an amount of light; prevent objects from getting into your eyes
Eyelids
The tough, outer layer that covers all of the eyeball except the iris and the pupil
Sclera
The tiny middle-ear bone that strengthens vibrations from the anvil as it knocks on the oval window of the inner ear
Stirrup
The three parts of the middle ear
Hammer, anvil, and stirrup
Send messages from your nose to your brain; your brain identifies the odor
Olfactory receptors
Hollow spaces in the skull bones; protect the eyes
Eye sockets
A medical doctor who specializes in eye diseases
Opthalmologist
The part of the ear that is completely filled with liquid; converts vibrations to nerve impulses
Inner ear
How to protect your sense of hearing
Never clean your ears with anything sharp. Blow air gently out your nose when you swim underwater. Don't blow your nose too hard. Avoid continual loud noises. If you know you are going to experience a loud noise, open your mouth and cover your ears. See a doctor if you have an earache.
Light-sensitive cells that detect shape and movement in dim light; distinguish different shades of black, gray, and white
Rods
Light-sensitive cells that distinguish color and sharp details when there is sufficient light
Cones
A thin membrane that lines the eyelids and covers the front part of the eyeball
Conjunctiva
The fluid-filled part of the inner ear that is shaped like a snail shell; contains the auditory nerve endings
Cochlea
How to protect your sense of sight
Work in a well-lighted area. Have regular eye examinations. Carry sharp, pointed objects with their points down. Never rub your eyes.