The Ear

Question 1

The ear is associated with what bone?

Answer 1

Temporal bone

Question 2

2 special sensory functions of the ear?

Answer 2

Hearing and balance

Question 3

The middle ear is connected to the nasopharynx by the ______

Answer 3

eustachian tube

Question 4

Function of the external ear?

Answer 4

Collects soundwaves and directs it towards the middle ear

Question 5

Function of the middle ear?

Answer 5

Conducts and amplifies vibrations towards the inner ear

Question 6

Function of the inner ear?

Answer 6

Converts the vibration or movement of fluid into action potentials

Question 7

The external ear is composed of what 2 things?

Answer 7

The external acoustic meatus (ear canal) and the pinna/ auricle

Question 8

The pinna is formed by _____1____ and attached to the ___2_____ It is ___3____

Answer 8

1) elastic cartilage
2) temporal bone
3) avascular and gains nutrients from the skin

Question 9

The external acoustic meatus lateral 1/3 is formed by ___1___ and the medial 2/3 by the ____2___ The medial end is marked by the ___3____ It is lined with skin which by produces ear wax by the ____4______

Answer 9

1) cartilage
2 petrous part of temporal bone
3) tympanic membrane
4) ceruminous glands

Question 10

Define the tympanic cavity?

Answer 10

narrow air filled chamber in the petrous portion of the temporal bone containing the apparatus for the middle ear

Question 11

Describe the two parts of the tympanic cavity?

Answer 11

The tympanic cavity proper (space directly internal to the tympanic membrane)
The epitympanic recess (space superior to the membrane)

Question 12

What is the function of the eustachian tube? What is the structure and how does it do this?

Answer 12

Equalise pressure between the middle ear and nasopharynx
Close to the ear there is an osseous portion, the cartilaginous portion is near the nasopharynx and this is typically closed only becoming patent during muscular contraction which allows it to equalise the pressure

Question 13

The opening of the eustachian tube is ________

Answer 13

anterior to the torus tobarius

Question 14

The mucosa of the middle ear is ______ with the nasal cavity through the eustachian tube

Answer 14

continuous

Question 15

The glossopharyngeal nerve provides sensory innervation to the mucosa of?

Answer 15

middle ear cavity, eustachian tubes, nasopharynx, oropharynx, palatine tonsils.

Question 16

Why can tonsillitis cause earache and earache cause throat pain?

Answer 16

The glossopharyngeal nerve provides sensory innervation to both areas and due to eustachian tube the lining is continuous

Question 17

What are the content of the tympanic cavity?

Answer 17

auditory ossicles
stapedius muscle
tensor tympani muscle
chordates tympani
Tympanic plexus of nerves

Question 18

The auditory ossicles provide a mobile chain of small bones across the tympanic cavity from the ______

Answer 18

tympanic membrane to oval window (opening into the inner ear)

Question 19

The auditory ossicles are the first bones to _______

Answer 19

ossify during development and are essentially mature at birth

Question 20

3 auditory ossicles from lateral to medial?

Answer 20

Malleus, Incus and stapes

Question 21

What is the smallest bone in the body?

Answer 21

stapes

Question 22

Joints between the auditory ossicles are?

Answer 22

Synovial

Question 23

What are the two muscles associated with the auditory ossicles?

Answer 23

Tensor tympani and stapedius

Question 24

Tensor tympani dampens sounds by _________ It is innervated by_________

Answer 24

reducing vibrations of the tympanic membrane- reduces noise from chewing
CNV3

Question 25

Stapedius reduces sounds by _________ It is innervated by_________

Answer 25

reducing vibrations of stapes on oval window

CNV7

Question 26

What does the inner ear consist of?

Answer 26

Membranous labyrinth containing endolymph which is suspended within the perilymph filled bony labyrinth. The bony labyrinth is contained within the otic capsule of the petrous part of the temporal bone and the otic capsule is made from bone denser than the rest of the petrous temporal bone.

Question 27

Describe the cochlea?

Answer 27

The shell shaped part of the bony labyrinth that contains the cochlear duct and is concerned with hearing

Question 28

Describe the 2 functional divisions of the membranous labyrinth?

Answer 28

1) Vestibular labyrinth for balance contains the utricle and saccule with the 3 semicircular ducts
2) cochlear labyrinth for hearing is composed of cochlear duct occupying the spiral canal of the cochlea

Question 29

The external ear is lined with ___1___

The middle ear is lined with ___2_____

Answer 29

1) epidermis

2) columnar mucosa

Question 30

The middle ear communicates with the ____1______ superiorly and the ____2_____ medially connects ______3______

Answer 30

1) mastoid air cells
2) Eustachian tube
3) middle ear to nasopharynx