The Ear

Question 1

label the outer ear

Answer 1

Question 2

label the tympanic membrane seen using otoscopy

Answer 2

Question 3

what type of joints are found between the ossicles?

Answer 3

synovial joints

Question 4

which ossicle is in contact with the tympanic membrane?

Answer 4

malleus

Question 5

which ossicle is in contact with the oval window?

Answer 5

stapes

Question 6

name two muscles related to the ossicles?

Answer 6

1. tensor tympani
2. stapedius

Question 7

what is the action of the tensor tympani?

Answer 7

pulls handle of malleus medially, tenses tympanic membrane
- reduces the amplitude of the tympanic membrane oscillations and thereby reduces sound transmission to the vestibular window.

Question 8

what is the action of the stapedius muscle?

Answer 8

pulls stapes posteriorly to tighten the annular ligaments to reduce oscillation and prevents excessive movement of the stapes

Question 9

name two areas with which the cavity of the middle ear communicates

Answer 9

1. nasopharynx - communicates with the middle ear via the eustachian tube.
2. mastoid air cells - communicated with the middle ear via the mastoid antrum and aditus.

Question 10

within which part of the temporal bone do the middle and inner ear lie?

Answer 10

petrous part

Question 11

the inner ear consists of a series of bone lined chambers called the?

Answer 11

bony labyrinth

Question 12

inside the bony labyrinth lies a series of membranous chambers called the?

Answer 12

membranous labyrinth

Question 13

what is the fluid that lies within the bony labyrinth called?

Answer 13

perilymph

Question 14

what is the fluid that lies withing the membranous labyrinth called?

Answer 14

endolymph

Question 15

what is the function of the cochlea and the semicircular canals?

Answer 15

cochlea plays a big role in hearing and semilunar canals are responsible for balance

Question 16

label the ear

Answer 16

Question 17

which structures compose the bony labyrinth?

Answer 17

cochlea
vestibule
three semi-circular canals

Question 18

which structures compose the membranous labyrinth?

Answer 18

cochlear duct, semi-circular ducts, utricle and saccule

Question 19

through which foramen does the facial nerve exit the posterior cranial fossa?

Answer 19

internal acoustic meatus

Question 20

which nerves pass through the internal acoustic meatus

Answer 20

facial and vestibulocochlear

Question 21

while in the middle ear cavity, what branch does the facial nerve give off?

Answer 21

chorda tympani

Question 22

label

Answer 22

Question 23

which nerve fibres does the chorda tympani transmit?

Answer 23

1. parasympathetic (preganglionic) efferent fibres destined for submandibular and sublingual salivary glands. These are secretomotor.
2. sensory fibres carrying the special sense of taste, supplying the anterior 2/3 of the tongue.

Question 24

what is the innervation of the tensor tympani muscle?

Answer 24

mandibular branch of trigeminal nerve