Chapter 13
The ear is considered part of the nervous system and has the following functions:
It allows hearing to occur by picking up sound waves and sending them to the brain. It helps maintain a person's balance.
Semicircular canals
Located behind the vestibule are three bony structures, filled with fluid, that also help to maintain balance.
Vestibule
The central portion of the inner ear, this structure contains the utricle and the saccule, which are membranous sacs that aid in maintaining balance.
Cochlea
This snail-shaped, bony structure contains endolymph and perilymph
Otorrhea
a discharge from the external ear.
Otosclerosis
a growth of spongy bone in the inner ear.
cochlear duct
a membranous structure that aids in the hearing process.
middle ear
also known as the tympanic cavity; found in the temporal bone and houses the auditory ossicles.
Incus
anvil
labyrinth
bony and membranous structures of the inner ear.
eustachian tube
connects the bony structures of the middle ear to the pharynx; also known as the auditory tube/pharyngotympanic tube The purpose of the eustachian tube is to equalize air pressure in the middle ear.
bony labyrinth
consists of bones that make up the inner ear.
cerumen
ear wax helps protect and lubricate the ear. In combination with the cilia, the cerumen helps to protect the eardrum from foreign objects.
Otalgia
earache
semicircular ducts
found in the middle ear; aid in balance.
Malleus
hammer
Otorrhagia
hemorrhage from the ear.
Membranous labyrinth
is a term used to describe the utricle, saccule, semicircular ducts, and cochlear ducts because these structures are all membranous structures.
auricle
known as the pinna or earlobe that allows sound waves to enter the ear canal
saccule
membranous sac that aids in maintaining balance.
endolymph
one of the auditory fluids found in the cochlea that aid in hearing.
perilymph
one of two auditory fluids found in the inner ear that aid in the transmission of sound.
Stapes
stirrup
ceruminous glands
sweat glands found in the external auditory canal. secrete ear wax
external auditory canal
the canal that allows sound waves to travel to the inner part of the ear; also known as the external auditory meatus.
tympanic membrane
the eardrum. separates the external ear from the middle ear The membrane transmits sound vibrations to the inner ear through the auditory ossicles
otitis externa
the inflammation of the external auditory canal.
utricle
the structure of the inner ear that aids in maintaining balance.
auditory ossicles
the three small bones that transmit sound waves.
organ of Corti
the true organ of hearing found in the cochlea.
external ear
the visible part of the ear, not within the structure of the skull.
cilia
tiny hairs along the external auditory canal. aid in transmitting the sound waves inward to other auditory structures
oval window
what separates the middle ear and inner ear.