Ear

Question 1

Big function of middle ear

Answer 1

Tympanic membrane transmits vibrations to oval window via ossicles

Question 2

Big function of inner ear

Answer 2

Impulses are generated and transmitted to brain by cochlear and vestibular nn.

Question 3

Cartilage of auricle/pinna

Answer 3

Elastic (hyaline)

Question 4

Glands in the external ear

Answer 4

Ceruminous glands: modified apocrine glands which make cerumen (ear wax)

Question 5

Tensor tympanic m.

Answer 5

Dampens chewing noise

Question 6

Auditory (Eustachian) tube is lined by?

Answer 6

Psuedo stratified columnar (airway epithelium) with goblet cells

Question 7

Eustachian tube connects?

Answer 7

Tympanic cavity and pharynx → equalizes air pressure in middle ear

Question 8

Guttural pouches in equine

Answer 8

Large diverticuli of auditory tubes → cools brain during exercise

Question 9

Osseous labyrinth is located inside what bone?

Answer 9

Petrous temporal b.

Question 10

3 compartments of the osseous labyrinth

Answer 10

1. Vestibule
2. Semicircular canals
3. Cochlea

Question 11

Parts of the vestibule

Answer 11

1. Round window
2. Oval window
3. Membranous sacs (utricle and saccule)

Question 12

Round window is closed by?

Answer 12

Secondary tympani membrane

Question 13

Oval window is closed by?

Answer 13

Footplate of stapes

Question 14

Utricle

Answer 14

Dorsal sac (semicircular canal side) → detects horizontal linear acceleration

Question 15

Saccule

Answer 15

Ventra sac (cochlea side) → detects vertical linear acceleration

Question 16

Perilymph

Answer 16

Between osseous and membranous labyrinth

Question 17

Endolymph

Answer 17

Inside membranous labyrinth

Question 18

Semicircular canals detect?

Answer 18

Rotational acceleration

Question 19

Ampulla / cristae ampullares

Answer 19

Bulge at extremity of semicircular canal → location of sensory epithelium

Question 20

3 apparati which detect acceleration (vestibular function)

Answer 20

1. Ampullae of SCC
2. Macula utriculus
3. Macula sacculus

Question 21

Hearing is detected by?

Answer 21

Organ of corti in cochlea

Question 22

3 things which all sensory epithelium has in common

Answer 22

1. Hair cells
2. Supporting cell
3. Gelatinous mass overlaying hair cells

Question 23

Basic structure of hair cells

Answer 23

Cilium + stereocilia

Question 24

3 places where sensory epithelium exists

Answer 24

1. Organ of corti
2. Cristae ampullaris
3. Maculae (utricle and saccule)

Question 25

Type I or II hair cell, which is thinner?

Answer 25

Type II

Question 26

Cupula

Answer 26

Gelatinous body on surface of sensory cells in crista ampullaris

Question 27

Gelatinous body in maculae

Answer 27

Contains otoliths (calcium protein) to enhance receptor stimulation

Question 28

3 compartments of cochlea

Answer 28

1. Scala vestibuli
2. Scala media
3. Scala tympani

Question 29

Which cochlear compartment contains endolymph?

Answer 29

Scala media

Question 30

Vestibular membrane

Answer 30

Separates scala vestibuli and scala media

Question 31

Basilar membrane

Answer 31

Separates scala tympani and scala media

Question 32

Lower frequency waves are registered in what part of the cochlea?

Answer 32

Apex

Question 33

Stria vascularis

Answer 33

Lateral wall of scala media → produces endolymph

Question 34

Organ of corti is located in?

Answer 34

Scala media

Question 35

2 types of hair cells in organ of corti

Answer 35

Outer sensory (3-5)

Inner sensory (1)

Question 36

Gelatinous body structure of organ of corti

Answer 36

Tectorial membrane → made up GAGs

Question 37

How does hearing work?

Answer 37

1. Movement of tectorial membrane is monitored by sensory cells
2. Info passed to spiral ganglion
3. CN 8