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Contains mechanoreceptors
◦ Translate movement of air into a series of nerve
impulses that the brain is able to interpret as sound
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Outer ear
Middle ear
Inner ear
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Pinna
Auditory Cannal
◦ Tiny hairs and sweat glands (ear wax)
◦ protection
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Tympanic membrane (ear drum)
Ossicles (3 smallest bones)
◦ Hammer (Malleus)
◦ Anvil (Incus)
◦ Stirrup (Stapes)
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Round window
Oval window
Eustachian tube
◦ Connects middle ear and nasopharynx
◦ Air pressure equalizes
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Cochlea
◦ hearing
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Vestibule
◦ Balance & equilibrium
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Semicircular canals
◦ Balance & equilibrium
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Filled with Fluid
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Sound waves enter the auditory canal
Cause the tympanic membrane to vibrate
Vibrations pass to the hammer (malleus),
anvil (incus), then stirrup (stapes) causing
them to move
Stirrup (Stapes) pass vibration to the
membrane of the oval window
Vibration is then passed through the cochlea
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Cochlea
◦ 3 canals
 Vestibular canal
 Cochlea canal
 Tympanic canal
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Sound waves travel through the canals to basilar
membrane (lower wall of cochlea canal)
Hairs in cochlea combine to form spiral organ
(organ of Corti)
These hairs move with the vibrations of sound
waves and synapse with fibres from the cochlea
and auditory nerve
Message is carried to the brain