inner ear

Question 1

what are the 2 parts of the inner ear labyrinth?

Answer 1

bony and membranous

Question 2

the _____ labyrinth is an enclosure for the ____ labyrinth

Answer 2

bony; membranous

Question 3

what is the membranous labyrinth surrounded by?

Answer 3

perilymph

Question 4

what are the 3 parts of the bony labyrinth?

Answer 4

cochlea
vestibule
semicircular canals/ducts

Question 5

what contains the cochlear duct?

Answer 5

cochlea- shaped like a snail

Question 6

what contains the utricle and saccule?

Answer 6

vestibule

Question 7

what contain the semicircular ducts?

Answer 7

lateral, anterior and posterior semicircular canals

Question 8

the endolymph within the membranous lymph includes what 2 structures?

Answer 8

cochlear labyrinth

vestibular labyrinth

Question 9

what connects the saccule with the cochlea?

Answer 9

ductus reuniens

Question 10

what is the central bony structure that the cochlea wraps around?

Answer 10

modiolus

Question 11

what is the cochlear cupula?

Answer 11

apex of the cochlea- directed anterolaterally

Question 12

what is the bony ridge that connects the cochlea to the modiolus?

Answer 12

lamina of the modiolus

Question 13

what are the 3 channels of the cochlea?

Answer 13

cochlear duct
scala vestibuli
scala tympani

Question 14

what is the channel that the scala vestibuli and scala tympani communicate called?

Answer 14

helicotrema

Question 15

as the stapes vibrates, where are vibrations transmitted?

Answer 15

scala vestibuli

Question 16

what forms the base of the scala vestibuli?

Answer 16

oval window

Question 17

what is the base of the scala tympani?

Answer 17

round window

Question 18

vibrations transmitted through the scala vestibuli pass where?

Answer 18

scala tympani via the helicotrema

Question 19

the cochlear duct is in the middle of what? what is above it and below it?

Answer 19

it is in the middle of the bony labyrinth with the scala vestibuli above and scala tympani below

Question 20

what is the cochlea filled with?

Answer 20

endolymph

Question 21

the vestibular membrane separates the cochlea from the?

Answer 21

scala vestibuli

Question 22

the basilar or spiral membrane separates the cochlea from the?

Answer 22

scala tympani

Question 23

hair cells in the spiral organ are covered by?

Answer 23

tectorial membrane

Question 24

what are the hair-like projections from the basilar/spiral membrane sensitive to?

Answer 24

frequency and amplitude

Question 25

what are the 2 sacs of the vestibular labyrinth?

Answer 25

saccule and utricle

Question 26

what are the 3 semicircular ducts of the vestibular labyrinth?

Answer 26

anterior, lateral, posterior

Question 27

what does the saccule communicate with?

Answer 27

cochlear duct

Question 28

the utricle is larger and communicates with?

Answer 28

all 3 semicircular ducts | saccule by way of utricosaccular duct

Question 29

the sense organs within the saccule and utricle are hairlike projections called?

Answer 29

maculae

Question 30

___ are bathed in endolymph. ______ float on endolymph

Answer 30

maculae; otoliths

Question 31

movement of the head causes what which elicits impulses?

Answer 31

otoliths to deflect the maculae

Question 32

what detects centrifugal and vertical accelerations?

Answer 32

utricle

Question 33

what detects linear accelerations?

Answer 33

saccule

Question 34

what are the sense organs within the semicircular ducts called?

Answer 34

crista

Question 35

where are the crista located?

Answer 35

ampulla of each duct

Question 36

the semicircular ducts are particularly sensitive to what type of accelerations?

Answer 36

rotational

Question 37

dendrites carrying info to the vestibular ganglion are collected into what 2 branches?

Answer 37

superior branch- larger (12,000 fibers) | inferior branch- (8,000 fibers)

Question 38

axons from the vestibular ganglion make up what nerve?

Answer 38

vestibular nerve

Question 39

what is the blood supply to the labyrinth?

Answer 39

Basilar artery- internal auditory branch | Posterior auricular artery- stylomastoid branch

Question 40

axons from the spiral ganglion make up what nerve?

Answer 40

cochlear nerve

Question 41

describe the nerve pathway of the cochlear nerve

Answer 41

cochlear nuclei--> superior olivary and trapezoid nuclei in MO--> lateral leminscus--> inferior colliculi and medial geniculate bodies--> temporal lobe (broadmann 41,42)

Question 42

describe nerve pathway of vestibular nerve

Answer 42

axons carried to vestibular nuclear complex of MO--> cerebellum