Exercise 25: Hearing and Equilibrium

Question 1

Anatomical structures of the external ear

Answer 1

Pinna
Lobule
External auditory canal
Ceruminous glands
Tympanic membrane

Question 2

Anatomical structures of the middle ear

Answer 2

Malleus
Incus
Stapes
Oval window
Auditory tube (pharyngotympanic)

Question 3

Anatomical Structures of the inner ear

Answer 3

Cochlea
Vestibule
Semicircular canals

Question 4

Pinna

Answer 4

Description: elastic cartilage covered with skin, “antenna”
Function: collects and directs sound waves into the external acoustic meatus

Question 5

Lobule

Answer 5

Earlobe

Question 6

External acoustic meatus

Answer 6

Description: short, curved tube filled with ceruminous glands
Function: transmits sound waves from the auricle to the tympanic membrane

Question 7

Ceruminous glands

Answer 7

Produce cerumen (earwax)

Question 8

Tympanic membrane

Answer 8

Description: thin connective tissue membrane that vibrates in response to sound
Function: transfers sound energy to middle ear ossicles

Question 9

Middle ear

Answer 9

A small air-filled chamber, the tympanic cavity

Question 10

Malleus

Answer 10

“Hammer”, attached to tympanic membrane

Question 11

Incus

Answer 11

“Anvil”, articulates with malleus and stapes

Question 12

Stapes

Answer 12

“Stirrup”, base fits into oval window

Question 13

Function of the auditory ossicles?

Answer 13

Transmit vibratory motion of eardrum to oval window.

Dampened by tensor tympani and stapedius muscles.

Question 14

Oval window

Answer 14

Description: membrane covered opening, stapes sits on it
Function: transmits vibrations from stapes to perilymph of scala vestibuli

Question 15

Auditory tube (pharyngotympanic tube)

Answer 15

Description: connects middle ear to nasopharynx
Function: equalizes the pressure in the middle ear cavity with the external air pressure so that the tympanic membrane can vibrate properly

Question 16

Tensor tympani and stapedius

Answer 16

Tensor tympani attaches to malleus.
Stapedius attaches to stapes.
Help attenuate the vibrations of the tympanic membrane and ossicles.
Contracts to lower amplitude of vibration and volume.
Contract when you’re speaking so your voice doesn’t seem overly loud to you.

Question 17

Bony labyrinth

Answer 17

Cavity in temporal bone that includes the semicircular canals, the vestibule, and the cochlea.
Filled with perilymph.

Question 18

Cochlea

Answer 18

A spiral, conical bony chamber.
Extends from anterior vestibule.
Coils around bony pillar called modiolus.
Contains cochlear duct.
Contains the organ of Corti (hearing receptor).

Question 19

Scala tympani

Answer 19

Terminates at round window

Contains perilymph

Question 20

Scala vestibuli

Answer 20

Contains perilymph

Question 21

Scala media

Answer 21

Contains endolymph

Question 22

Conduction deafness

Answer 22

Something hampers sound conduction to fluids of inner ear (impacted earwax, perforated eardrum)

Question 23

Sensorineural deafness

Answer 23

Results from damage to neural structures

Question 24

Tinnitus

Answer 24

Ringing in the ears without auditory stimuli

Question 25

Meniere’s Syndrome

Answer 25

Labyrinth disorder that affects the cochlea and semicircular canals, causing vertigo, nausea, and vomitting

Question 26

Vestibular receptors monitor…

Answer 26

Static equilibrium

Question 27

Semicircular canals monitor…

Answer 27

Dynamic equlibrium

Question 28

Uttricular hair cells respond to…

Answer 28

Horizontal movement

Question 29

Saccular hair cells respond to…

Answer 29

Vertical movement

Question 30

Static equilibrium

Answer 30

Monitoring process of head position and acceleration in a straight line

Question 31

Dynamic equilibrium

Answer 31

Monitoring process of rotational acceleration of head