Lecture 20 - Special Senses: Ear

Question 1

function of pinna

Answer 1

collect sound waves

Question 2

the auditory canal skin is innervated by CN __?

containing? (3)

Answer 2

X (vagus)

ceruminous glands (wax)

sebaceous glands

hairs

Question 3

tympanic membrane is composed of what

Answer 3

2 layers of epithelium fused together

Question 4

1. lateral boundary of middle ear =
2. medial boundary of middle ear =
3. superior boundary of middle ear =
4. posterior boundary of middle ear =
5. anterior boundary or middle ear =

Answer 4

1. tympanic membrane
2. bony wall separating mid and inner ear
3. petrous portion of temporal bone

4 pneumatized (mastoid antrum)

5. opening of eustachian tube

Question 5

auditory ossicles are (3) and what do they do

tensor tympani muscle attaches to ___

stapedius muscle attached to ___

Answer 5

malleus, incus, stapes & carry vibrations from ear drum to oval window

malleus

stapes

Question 6

tympanic reflex

___ places tension across the ear drum

___ locks down the ossicular chain

= dampens vibration from ___ sounds

Answer 6

tensor tympani

stapedius

loud

Question 7

auditory (eustachian) tube

1. connects __ to ___
2. supported by ___ & ___
3. ___ pressure across tympanic membrane

Answer 7

1. middle ear to pharynx
2. muscle and cartilage
3. equalizes

Question 8

inflammation to auditory tube

1. an inflamed auditory tube will ___
2. ___ builds up & ___ is painful
3. threatens the ___ and sense of ___\___

why do kids get ear infections

Answer 8

1. swell shut
2. fluid, pressure
3. ear drum, hearing/balance

they’re auditory tube is horizontal so it fills with fluid. when you’re and adult it gets an angle during puberty so it drains better

Question 9

myringotomy is what

if not performs, infection can spread …

1. mastoiditis =
2. otitis media =
3. labyrinthitis =

Answer 9

surgical insertion of a tube that releases fluid from mid ear

1. infection of mastoid air cells
2. infection or middle ear
3. infection of inner ear

Question 10

inner ear

1. osseous labyrinth = ___
   a. ___ canals in ___ portion of the ___ bone
   b. ___ labyrinth is housed within the ___ labyrinth
2. membranous labyrinth = ___
   a. ___ tubes/chambers within ___ labyrinth
   b. ___ fills each canal/chamber
   c. ___ is the space between oss and mem labyrinths
3. hair cell = functional unit of ___ and ___
   a. hair cells are located throughout ___ labyrinth
   b. vibration/movement of stereocilia = ___

Answer 10

1. BONE
   a. boney, petrous, temporal
   b. membranous, boney
2. MEMBRANE
   a. hollow, osseous
   b. endolymph
   c. perilymph
3. hearing and balance
   a. membranous
   b. signal

Question 11

vestibular portion of the inner ear

semicircular canals

1. three canals = __ & __ & ___
   a. filled with ___
2. each canal has a swelling at its base (___)
3. ___ are equipped with hair cells
   a. hair cells aligned in a ridge = ___
   b. tips of hair cells are embedded in gel = ___
4. ___ are distorted by ___ movement
   a. sensitive to changes in ____ (rotation)
5. vestibular part of CN __?

Answer 11

1. lateral, anterior, posterior
   a. endolymph
2. ampulla
3. ampullae
   a. crista
   b. cupula
4. cupulae, endolymph
   a. position
5. VIII (8)

Question 12

vestibular complex

1. utricle and saccule each have a ___
2. ___ equipped with ___ cells covered by thick gel
3. gel is ornamented with ___ carbonate crystals
4. otoliths provide mass across top of ___ cells
5. differential nonevent of gel and head = ___
   a. = gravity, tilt, and linear acceleration

Answer 12

1. macula
2. maculae, hair
3. calcium
4. hair
5. signal

Question 13

vertigo = ___ overload

1. steady movement includes ___ to flow
2. flow can be interrupted by abrupt __ or ___
3. causes ___ and ____

Answer 13

receptor

1. endolymph
2. stop or change
3. dizziness and nausea

Question 14

vertigo - mismatch of audio/visual information

1. vestibule apparatus senses ___
2. __ system says “stationary”

3 vestibular nuclei in the ___ are confused

4. causes __ and ___

Answer 14

1. movement
2. visual
3. brain stem
4. dizziness and nausea

Question 15

vertigo and vestibular nystagmus

1. steady movement induced ___ to flow

if movement continues:
a. ___ stabilizes
b. eyes get accustomed to the tracking of ___ objects
c. eye and vestibular systems are ___

if movement stops suddenly
a. ___ is suddenly re accelerated
b. __ and __ ensues
c. eyes will ___ (nystagmus) in direction of spin
d. continues until the ___ calms down

Answer 15

1. endolymph

a. endolymph
b. moving
c. interconnected

a. endolymph
b. dizziness and nausea
c. race
d. endolymph

Question 16

cochlear portion of the inner ear

SOUND

1. ___ of air molecules (sound waves)
2. high pitched tones = __ ___ vibration
   a. high frequencies have __ wave lengths
   b. short wave lengths travel __ distances (pin drop)

3 low pitched tones = __ __ vibration
a. low frequencies have __ wave lengths
b. long wave lengths travel __ distance (truck)

Answer 16

1. vibration
2. high frequency
   a. short
   b. short
3. low frequency
   a. long
   b. long

Question 17

hearing ability depends on size of (4)

Answer 17

pinnae

tympanum

ossicles

cochlea

Question 18

what region of the inner ear is responsible for hearing

Answer 18

cochlea

Question 19

coiled tube resembling a snails shell is

Answer 19

cochlear duct

Question 20

floor of cochlear duct =

Answer 20

basal membrane

Question 21

cochlear ducts lies between 2 other ducts

1. ___ duct: oval window to the helicotrema
2. ___ duct: helicotrema to the round window

both of these ducts are filled with ___

helicotrema =

Answer 21

1. vestibular
2. tympanic

perilymph

tip of cochlea

Question 22

2 membrane covered “holes” of note:

a. oval window for the stapes (___ duct)

b. round window (___ duct)

Answer 22

a. vestibular

b. tympanic

Question 23

organ of corti = ___ receptor

1. ___ cells disturbed along basal membrane
2. tips of hair cells in contact with __ membrane
3. distortion of basal membrane/hair cells = ___
4. signal > cochlear part of CN __?

Answer 23

auditory

1. hair
2. tectorial
3. signal
4. VIII (8)

Question 24

sound transduction

1. pinna
3. tympanic membrane
5. incus
7. oval window
9. cochlear duct

10.

Answer 24

2. external acoustic meatus
3. malleus
4. stapes
5. vestibular/tympanic duct
6. basilar membrane

Question 25

combination of wavelength/location = __

1. high pitch/short wavelength/short distance = ___ of basilar membrane
2. low pitch/long wavelength/long distance = __ of basilar membrane

Answer 25

sound

base

tip