objective 10 Flashcards
Has a characteristic shape - funnels sound waves into the external
auditory canal
Consists of moveable cartilage and skin
* Ends at the tympanic membrane
* Lined with glands that secrete cerumen (yellow, waxy material)
* Cerumen forms a sticky barrier that helps keep foreign
bodies from entering the ear and reaching the tympanic
membrane
* Cerumen moves out to the meatus by the movements of
chewing and talking
external ear
outer third of the canal
cartilage
inner two thirds
bone covered by thin sensitive skin
Separates the external ear and the middle ear
* Oval, slightly concave, and is slightly pulled in the center by the
malleus
tympanic membrane
what are the 3 parts of the malleus
umbo
manubrium
short process
small, slack superior section of the tympanic membrane
pars flaccida
remainder of the tympanic membrane which is thicker and
more taunt
pars tensa
outer fibrous rim
annulus
tiny air-filled cavity inside the
temporal bone
* Contains auditory ossicles: malleus, incus,
stapes
* Has several openings:
* Outer ear
* Inner ear
* Eustachian tube
middle ear
covered by tympanic membrane
outer ear
oval window and the round window
inner ear
connects the middle ear to the nasopharynx; allows the passage of air
eustachian tube
what are the 3 functions of the middle ear?
Conducts sound vibrations -conducts them from the outer ear
to the central hearing apparatus in the inner ear
* Protects the inner ear - reduces the amplitude of sound
* Eustachian tube allows equalization of air pressure on each
side of the eardrum - prevents rupture of the membrane
Embedded in bone, contains the Bony Labyrinth:
* Vestibule and semicircular canals:
* Cochlea:
* is not accessible to direct examination, however
the functions of the inner ear can be assessed.
inner ear
holds the sensory organs for equilibrium and hearing
bony labyrinth
constitute the vestibular apparatus
vestibule and semicircular canals
contains central hearing apparatus
cochlea
what are the 3 divisions of the auditory system?
peripheral
brain stem
cerebral cortex