The ear

Question 1

What are the three components of the outer ear

Answer 1

Auricle, External auditory meatus, Tympantic membrane

Question 2

What is the structure of the auricle

Answer 2

integument overlying elastic cartilage

• integument is thin, keratinized stratified squamous epithelium
• Hair follicles can be observed in the dermis

Question 3

The auricle is the

Answer 3

pinna of the ear

Question 4

The outer third of the ear canal is composed of

Answer 4

elastic cartilage

Question 5

The inner two thirds of the ear canal is composed of

Answer 5

bone

Question 6

The lining of the ear canal is

Answer 6

stratified squamous epithelium with sebaceous glands and ceruminous glands (modified sebaceous glands)

Question 7

What separates the external auditory meatus form the middle ear

Answer 7

The tympanic membrane

Question 8

The core of the Tympanic membrane is formed from

Answer 8

Vacularized, innervated CT

Question 9

The external surface of the tympanic membrane is covered by

Answer 9

thin skin

Question 10

The internal surface of the tympanic membrane is covered by

Answer 10

simple cuboidal epithelium

Question 11

The middle ear (tympanic cavity) is composed of

Answer 11

Auditory ossicles: Malleus, Incus, Stapes
Openings: oval window, round window
Muscles: Tensor tympani, Stapedius

Question 12

____ attaches to the internal surface of the tympanic membrane

Answer 12

Malleus

Question 13

The malleus articulates with the

Answer 13

Incus (anvil)

Question 14

What is the intermediate bone between the stapes and malleus

Answer 14

Incus (anvil)

Question 15

What is the third auditory ossicle in the series

Answer 15

Stapes

Question 16

Why is the stapes shaped like a stirrup

Answer 16

due to the opening for the stapedial artery

Question 17

The stapes inserts onto the

Answer 17

oval window

Question 18

The oval window opens into the

Answer 18

scala vestibuli

Question 19

The round window is a membrane covered region at the end of the

Answer 19

scala tympani

Question 20

Where does the tensor tympani insert

Answer 20

on the malleus

Question 21

Where does the stapedius insert

Answer 21

on the stapes

Question 22

What is the purpose of the tensor tympani and stapedius

Answer 22

These muscles contract reflexively in response to loud sounds in order to dampen the vibrations of the auditory ossicles

Question 23

The inner ear consists of what regions

Answer 23

Bony labyrinth
membranous labyrinth
Vestibular organ
Auditory organ

Question 24

Complex system of canals and chambers embedded in the petrous portion of the temporal bone

Answer 24

Bony labyrinth

Question 25

The bony labyrinth is filled with

Answer 25

High-sodium content perilymph

Question 26

The bony labyrinth consists of

Answer 26

semicircular canals cochlea Scala Vestibuli Scala Tympani

Question 27

The membranous labyrinth is a

Answer 27

complex system of membranous structures embedded within the chambers of the bony labyrinth

Question 28

The membranous labyrinth is filled with

Answer 28

high-potassium content endolymp

Question 29

Endolymph is high in

Answer 29

potassium content

Question 30

Perilymph is high in

Answer 30

Sodium content

Question 31

Patches of sensory structures that respond to changes in position

Answer 31

Vestibular organs

Question 32

The vestibular organs consist of

Answer 32

Maculae of the saccule and utricle | cristae ampullaris of the semicircular canals

Question 33

Epithelium of the Maculae of Saccule and Utricle

Answer 33

- Columnar supporting cells - Vestibular hair cells - Numerous stereocilia - Single kinocilium

Question 34

Vestibular hair cells are in contact with

Answer 34

afferent nerve endings

Question 35

The otolithic membrane is a characteristic of

Answer 35

Maculae of Saccule and Utricle

Question 36

Gelatinous layer containing calcium carbonate crystals called otoliths that overlie the epithelium

Answer 36

Otolithic membrane

Question 37

Components of the membranous labyrinth

Answer 37

Utricle Saccule Ampullae, which contains the crista ampullaris Semicircular ducts (which open into the utricle) Cochlea

Question 38

Sterocilia of the vestibular hair cells of the Saccule and Utricle are embedded in

Answer 38

The otolithic membrane

Question 39

Movements of the hair cells displaces the otolithic membrane and causes

Answer 39

a sensory impulse

Question 40

Important characteristics of the cristae ampullares of semicircular ducts epithelium

Answer 40

Columnar supporting cells | Hair cells

Question 41

What is the Cupula

Answer 41

It is a gelatinous layer overlying the epithelium of cristae Ampullares (note that it is very similar to otolithic membrane but without ostoliths (calcium carbonate crystals))

Question 42

Movement of the hair cell in the cupula creates

Answer 42

shear forces between the semicircular canals and the contained fluid this displaces the cupula and causes the stereocilia to bend

Question 43

What are the sensory receptors of the membranous labyrinth

Answer 43

cristae ampullares macula utriculi macula sacculi organ of Corti, which is in the Cochlea

Question 44

what anchors the otolithic membrane to the sensory epithelium

Answer 44

Otogelin

Question 45

The auditory organ (cochlea) consists of

Answer 45

cochlear duct | Organ of corti

Question 46

The coclear duct (scala media) consists of

Answer 46

``` Scala vestibuli Scala tympani vestibular membrane basilar membrane stria vascularis ```

Question 47

The coclear duct (scala media) divides the bony cochlea into

Answer 47

scala vestibuli and scala tympani

Question 48

The vestibular membrane forms the ____ of the cochlear duct

Answer 48

roof

Question 49

The basilar membrane forms the ____ of the cochlear duct

Answer 49

floor

Question 50

What forms the lateral aspect of the cochlear duct (scala media)

Answer 50

Stria vascularis

Question 51

The stria vascularis participates in the formation of the

Answer 51

Endolymph

Question 52

What lies on the basilar membrane of the cochlear duct

Answer 52

Organ of Corti

Question 53

The potential difference between the perilymph and the endolymph is

Answer 53

+80 mV

Question 54

The resting intracellular potential of a hair cell is

Answer 54

-70 mV