PART 2: THE EAR: HEARING AND BALANCE

Question 1

move fluid to stimulate hearing receptors, whereas gross movements of the head disturb fluids surrounding the balance organs.

Answer 1

sound vibrations

Question 2

Receptors that respond to such physical forces are called

Answer 2

mechanoreceptors

Question 3

is composed of the auricle and the external acoustic meatus.

Answer 3

The external ear, or outer ear

Question 4

shell-shaped structure surrounding the auditory canal opening.

Answer 4

The auricle, or pinna

Question 5

is a short, narrow chamber carved into the temporal bone of the skull

Answer 5

The external acoustic meatus (or auditory
canal)

Question 6

skin-lined walls, which secrete waxy yellow cerumen, or earwax

Answer 6

ceruminous glands

Question 7

provides a sticky trap for foreign bodies and
repels insects.

Answer 7

cerumen, or earwax

Question 8

Sound waves entering the auditory canal eventually hit the (which separates the external from the middle ear.)

Answer 8

tympanic membrane or eardrum

Question 9

is a small, air-filled, mucosa-lined cavity within the temporal bone. It is flanked laterally by the eardrum and medially by a bony wall with two openings, the oval window and the inferior, membrane-covered round window

Answer 9

The middle ear cavity, or tympanic cavity

Question 10

runs obliquely downward to link the middle ear cavity with the throat, and the mucosae lining the two regions are continuous.

Answer 10

pharyngotympanic tube, or auditory tube

Question 11

Inflammation of the middle ear, is a fairly common result of a sore throat, especially in children, whose pharyngotympanic tubes run more horizontally.

Answer 11

otitis media

Question 12

The tympanic cavity is spanned by the three smallest bones in the body, which transmit the vibratory motion of the eardrum to the fluids of the inner ear

Answer 12

ossicles

Question 13

The internal ear is a maze of bony chambers
called the

Answer 13

bony labyrinth, or osseous labyrinth

Question 14

The three subdivisions of the bony labyrinth are the spiraling

Answer 14

1. Cochlea
2. Vestibule (is situated between)
3. Semicircular canals

Question 15

These bones, named for their shape

Answer 15

1. Hammer or Malleus
2. Anvil or Incus
3. Stirrup or Stapes

Question 16

The bony labyrinth is filled with a plasma-like
fluid

Answer 16

perilymph

Question 17

Suspended in the perilymph, a system of membrane sacs that more or less follows
the shape of the bony labyrinth.

Answer 17

membranous labyrinth

Question 18

The membranous labyrinth itself contains a thicker fluid called

Answer 18

endolymph

Question 19

what is does is respond (frequently without our awareness) to various head movements.

Answer 19

equilibrium

Question 20

The equilibrium receptors of the inner ear, collectively

Answer 20

vestibular apparatus

Question 21

Within the membrane sacs of the vestibule are
receptors that are essential to our sense of equilibrium

Answer 21

maculae

Question 22

maculae “spots” that are essential to our sense of

Answer 22

sense of equilibrium

Question 23

report on changes in the position of the head in space with respect to the pull of gravity when the body is not moving

Answer 23

maculae

Question 24

Each macula is a patch of receptor (hair) cells with their “hairs” embedded, a gelatinous mass studded with otoliths

Answer 24

otolithic membrane

Question 25

tiny stones made of calcium salts that is studded with

Answer 25

otoliths

Question 26

receptors, found in the semicircular canals, respond to angular or rotational movements of the head rather than to straight-line movements.

Answer 26

dynamic equilibrium

Question 27

are multiple receptor regions, which consists of a tuft of hair cells covered with a gelatinous cap

Answer 27

crista ampullaris

Question 28

a gelatinous cap that covered tuft of hair cells in crista ampullaris

Answer 28

cupula

Question 29

the endolymph-containing membranous labyrinth of the cochlea is within

Answer 29

cochlear duct

Question 30

the endolymph-containing membranous labyrinth of the cochlea , which contains the hearing receptors, or hair cells

Answer 30

spiral organ of Corti

Question 31

Sound waves that reach the cochlea through vibrations of the eardrum, ossicles, and oval window set the cochlear fluids into

Answer 31

motion

Question 32

is increased by the lever activity of the ossicles as the sound waves are transmitted by the ossicles from the eardrum to the oval window

Answer 32

their force (amplitude)

Question 33

nearly the total force exerted on the much larger eardrum reaches the tiny oval window, which in turn sets the fluids of the inner ear into motion, and these pressure waves set up vibrations in the

Answer 33

basilar membrane

Question 34

The receptor cells, positioned on the basilar membrane in the spiral organ of Corti, are stimulated by the vibrating movement of the basilar membrane against the gel-like

Answer 34

tectorial membrane

Question 35

the hair cells transmit impulses along a (a division of cranial nerve VIII—the vestibulocochlear nerve) to the auditory cortex in the temporal lobe, where interpretation of the sound, or hearing, occurs.

Answer 35

cochlear nerve

Question 36

is defined as hearing loss of any degree—from a slight loss to a total inability to hear sound.

Answer 36

deafness

Question 37

a ruptured eardrum, and otitis media (inflammation of the middle ear)

Answer 37

otosclerosis

Question 38

occurs when there is degeneration or damage to the receptor cells in the spiral organ of Corti, to the cochlear nerve, or to neurons of the auditory cortex.

Answer 38

Sensorineural deafness

Question 39

The exact cause of this condition is not fully known, but suspected causes are arteriosclerosis, degeneration of cranial nerve VIII, and increased pressure of the inner ear fluids.

Answer 39

Ménière’s syndrome