17a. Inner ear. Bony and membranous labyrinth.

Question 1

What is the location of the inner ear?

Answer 1

In the petrous part of the temporal bone.

Question 2

What are the parts of the inner ear?

Answer 2

1. bony labyrinth
2. membranous labyrinth
3. ganglia and final branches of the vestibulocochlear nerve (VIII.)

Question 3

What are the functions of the inner ear?

Answer 3

1. hearing (cochlea, spiral organ of Corti)
2. balance
3. Spatial orientation

Question 4

The bony (osseous) labyrinth
-> Identify

Answer 4

Question 5

The bony (osseous) labyrinth
-> Identify

Answer 5

Question 6

What are the Bony limbs (crura) of semicircular canals? (there are 5)

Answer 6

• 3 ampullary crura
• 1 simple crus
• 1 common crus

Question 7

Left osseous labyrinth, lateral view
-> Identify

Answer 7

Question 8

Left osseous labyrinth, lateral view
-> Identify

Answer 8

Question 9

Left osseous labyrinth, lateral view
-> Identify

Answer 9

Question 10

What are Maculae cribrosae?

Answer 10

perforated areas for entering the branches of the vestibular
nerve
-> They haver superior, media, inferior part

Question 11

Innervation of Maculae cribrosae

Answer 11

1. Sup - utriculoampullar nerve
2. Media - Saccular nerve
3. Inferior - Posterior ampullary nerve

Question 12

Interior of the vestibule
-> Identify

Answer 12

Question 13

The cochlea II.
-> Identify

Answer 13

Question 14

The cochlea I.
-> Identify

Answer 14

Question 15

The cochlea I.
-> Identify

Answer 15

Question 16

The spiral canal of cochlea
-> Identify

Answer 16

Question 17

The spiral canal of cochlea
-> Identify

Answer 17

Question 18

The spiral canal of cochlea
-> Identify

Answer 18

Question 19

The spiral canal of cochlea
-> Identify

Answer 19

Question 20

The spiral canal of cochlea
-> Identify

Answer 20

Question 21

Arterial supply of the membranous labyrinth

Answer 21

Question 22

Venous supply of the membranous labyrinth

Answer 22

labyrinthine veins, v. of aqueduct of vestibule,v. of aqueduct of cochlea → inf. petrosal sinus → sigmoid sinus

Question 23

The role of Perilymph

Answer 23

fills the bony labyrinth protecting the membranous one

Question 24

Endolymph is drained by ___

Answer 24

by the endolymphatic duct into the dura matter venous sinuses

Question 25

Perilymph is produced by ____

Answer 25

by the microvasculature of the periosteum

Question 26

Perilymph is drained by ___

Answer 26

the perilymphatic duct into the subarachnoideal space

Question 27

The role of Perilymph

Answer 27

fills the bony labyrinth protecting the membranous one

Question 28

The role of Endolymph

Answer 28

fills the membranous labyrinth,

Question 29

Endolymph is produced by __

Answer 29

the stria vascularis (cochlea) and by the dark cells in semicircular duct

Question 30

The role of Perilymph

Answer 30

fills the bony labyrinth protecting the membranous one

Question 31

Sound waves in the perilymph, pressure equilibration

Answer 31

base of the stapes→fenestra vestibuli → scala vestibuli perilymph → cochlear duct and helicotrema → scala tympani perilymph → fenestra rotunda → secondary tympanic membrane

Question 32

What are the 2 Receptors in the vestibular system?

Answer 32

1. Cristae ampullares 2. Maculae staticae

Question 33

Receptors in the vestibular system -> Describe the position of Cristae ampullares

Answer 33

* in the ampullae of semicircular ducts * the ridge of the crista is always perpendicular to the long axis of the duct

Question 34

Receptors in the vestibular system -> Describe position of macula

Answer 34

* in the utricle and saccule * they lie in a perpendicular plane to each other

Question 35

Receptors in the vestibular system -> The role of macula

Answer 35

detect linear acceleration, tilt of the head and gravity

Question 36

Receptors in the vestibular system -> The role of Cristae ampullares

Answer 36

detect angular acceleration of the head.

Question 37

What are the hair cells?

Answer 37

secondary sensory cell, mechanoreceptor

Question 38

Differences between stereo cilia and kinoclium

Answer 38

Stereocilia Kinocilium

Question 39

Describe the basal part of the vestibular hair cells

Answer 39

* cell nucleus, synaptic vesicles (glutamate) * synapses with afferents (peripheral processes of bipolar ganglionic cells) * efferent fibers from the brain, modulation of sensitivity

Question 40

The structure of the macula -> Identify

Answer 40

Question 41

The structure of the ampullary crest -> Identify

Answer 41