auditory nerve: sends the sound signal to the brain.

auricle (pinna): the most visible part of the ear, the concave elastic cartilaginous structure attached to the surface of the skull.

cochlea: the part of the inner ear containing the sensory mechanism of hearing.

ear canal (external auditory meatus): the passageway or tube extending from the auricle to the tympanic membrane through which sound waves travel. It is composed of an outer cartilaginous portion and an inner bony portion.

eardrum (tympanic membrane): the thin, concave, membrane, the edges of which are held in place by a bony ring, which closes the inner end of the external auditory meatus.

eustachian tube: air duct from the nasopharynx which enters the anterior wall of the middle ear at its lowest point.

incus (anvil): the middle of the three bones comprizing the ossicular chain and serves to join the malleus and stapes.

malleus (hammer): the first and largest bone in the ossicular chain. The handle (manubrium) is attached to the eardrum and serves to activate the saddleshaped surface on the body of the incus to transmit sound waves.

ossicles (malleus, incus, stapes): the three smallest bones in the body.

semicircular canals: three looped bony tubes, the anterior vertical, posterior vertical, and horizontal or lateral canals, located in planes at right angels to each other and opening into teh vestibule. They help an individual to maintain his sense of balance.

stapes (stirrup): the third and smallest bone in the ossicular chain, and articulates with the incus and moves its footplate into the oval window to transmit sound waves from the middle ear into the inner ear. It controls the loudness of sounds by being able to rotate on its transverse axis and diddipate some of the sound energy.