Special Sense Organs Part 5

Question 1

What two arteries carry the blood supply to the middle ear?

Answer 1

anterior tympanic branch of the internal maxillary artery and the tympanic branch of the internal carotid artery

Question 2

What nerve provides the sensory supply to the middle ear?

Answer 2

tympanic nerve of CN IX

Question 3

What nerves provide motor supply to the middle ear?

Answer 3

Nerve to the stapedius of the facial nerve and the medial pterygoid nerve of the mandibular division (supplies tensor tympani)

Question 4

What nerves provide sympathetic supply to the middle ear?

Answer 4

caroticotympanic nerves

Question 5

What nerves carry vasomotor and secretomotor fibers from the superior cervical ganglion to the middle ear by way of the internal carotid plexus?

Answer 5

caroticotympanic nerves

Question 6

What are the two parts of the labyrinth (inner ear)?

Answer 6

bony and membranous

Question 7

What is the enclosure for the membranous labyrinth?

Answer 7

bony labyrinth

Question 8

What is the membranous labyrinth surrounded by within the bony labyrinth?

Answer 8

perilymph

Question 9

What are the 3 parts of the bony labyrinth?

Answer 9

cochlea, vestibule, and semicircular canals

Question 10

What part of the bony labyrinth is shaped like a snail shell and contains the cochlear duct?

Answer 10

cochlea

Question 11

What part of the bony labyrinth contains the saccule and utricle?

Answer 11

vestibule

Question 12

What part of the bony labyrinth is divided into the lateral, anterior, and posterior and contains the semicircular ducts?

Answer 12

semicircular canals

Question 13

T/F: the membranous labyrinth is bathed in endolymph and contains perilymph.

Answer 13

False; bathed in perilymph, contains endolymph

Question 14

What are the 2 main parts of the membranous labyrinth?

Answer 14

cochlear labyrinth and vestibular labyrinth

Question 15

T/F: the cochlear labyrinth contains the utricle, saccule, semicircular ducts, utricosaccular duct, endolymphatic duct, endolymphatic sac, and ductus reuniens.

Answer 15

False; these are contained in the vestibular labyrinth; the cochlear labyrinth only contains the cochlear duct

Question 16

The bony part of the cochlea consists of a tube coiled around a cones shaped central bony structure call what?

Answer 16

the mediolus

Question 17

How many times does the cochlea wrap around the modiolus?

Answer 17

2.5-2.75 times

Question 18

What is the term for the apex of the cochlea which is directed anteriolaterally?

Answer 18

the cochlear cupula

Question 19

What is the name of the bony ridge that connects the cochlea to the modiolus?

Answer 19

the lamina of modiolus

Question 20

What 3 channels make up the cochlea?

Answer 20

the cochlear duct, the scala vestibuli and the scala tympani

Question 21

Where does the cochlear duct end?

Answer 21

at the apex of the cochlea

Question 22

How do the scala tympai and the scala vestibuli communicated with each other?

Answer 22

at the apex through a channel called the helicotrema

Question 23

T/F: the scala vestibuli is above the cochlear duct and filled with endolymph.

Answer 23

False; filled with perilymph

Question 24

What forms the base of scala vestibuli allowing for vibrations to be transmitted from the stapes into the scala vestibuli?

Answer 24

oval window

Question 25

The scala tympani is below the cochlear duct and vibrations from the scala vestibuli pass to the scala tympani via what structure? What is the base of the scala tympani?

Answer 25

helicotrema; | round window

Question 26

What structure is in the middle of the bony labryrinthfilled with endolymph with the scala vestibule above and the scala tympani below?

Answer 26

cochlear duct

Question 27

What structure is attached to the lamina of the modiolus, anchored to the outer wall of the cochlea by the spiral ligament, and separated from the scala vestibuli by the vestibular membrane?

Answer 27

cochlear duct

Question 28

What separates the cochlear duct from the scala tympani?

Answer 28

the basilar or spiral membrane

Question 29

Where is the spiral organ located? what is it attached to?

Answer 29

on the floor of the cochlear duct, attached to the basilar/spiral membrane

Question 30

What structure of the inner ear has numerous hair-like projections superiorward that are sensitve to frequency and amplitude of sound waves that enter cochlea?

Answer 30

spiral organ

Question 31

What are the hair cells of the spiral organ covered by?

Answer 31

tectorial membrane

Question 32

What are the hair like projections of the spiral organ projecting from?

Answer 32

basilar/spiral membrane

Question 33

Info is conveyed from receptor cells in the inner ear to the primary sensory neurons. Where are the cell bodies of these neurons located?

Answer 33

in the spiral ganglion