auditory apparatus

Question 1

Tympanic membrane divides the

Answer 1

external and middle ear

Question 2

joins middke ear to the nasopharynx

Answer 2

pharyngotympanic tube

Question 3

ear (anterior view)

Question 4

components of external ear

Answer 4

auricle

external acoustic meatus

tympanic membrane

Question 5

what consists of cartilage and fibrous tissue (lobule), and directs sound waves towards the external auditory meatus?

Answer 5

auricle

Question 6

What canal leads inwards from auricle to tympanic membrane.

Answer 6

• external acoustic meatus
• Lateral 1/3rd is cartilaginous and lined with skin that is continuous with auricular skin. This portion produces cerumen (earwax)
• Medial 2/3rd is bony and lined with skin continuous with the tympanic membrane

Question 7

What component of the external ear is ~1 cm diameter, thin, oval semitransparent membrane at the medial end of external acoustic meatus?

Answer 7

• tympanic membrane
• Covered with skin externally and mucous membrane internally
• Movement of the membrane is passed to the auditory ossicles

Question 8

*external ear

Question 9

blood supply and nerves to the** auricle**

Answer 9

• Blood supply
  
  • Superficial temporal
  • Posterior auricular
• Nerves
  
  • Great auricular
  • Auriculotemporal (CN V3)

Question 10

nerves to the external meatus & tympanic membrnae

Answer 10

• Nerves
  
  • Auriculotemporal
  • Vagus
  • Glossopharyngeal (internal surface of tympanic membrane)

Question 11

narrow air-filled chamber in the petrous part of the TB

Answer 11

middle ear

Question 12

*middle ear

Question 13

parts of the middle ear

Answer 13

• Tympanic cavity proper: space directly internal to tympanic membrane
• Epitympanic recess: space superior to the membrane

Question 14

components of middle ear include:

Answer 14

pharyngotympanic tube

auditory ossicles (malleus, incus, stapes)

and mm’s associated with auditory ossicles

Question 15

pharyngotympanic tube

Answer 15

Connects tympanic membrane to the nasopharynx. Posterolateral 1/3rd is bony, rest 2/3rd is cartilaginous. Equalizes pressure in middle ear with atmospheric pressure, allowing free movement of the tympanic membrane.

Question 16

auditory ossicles

Answer 16

• transfer sound from the tympanic membrane to the oval window (an oval opening on the labyrinthine wall of tympanic cavity)
• Labyrinthine wall: separates the middle and inner ear
• Auditory ossicles are first bone to be ossified during development and are practically mature at birth
• Malleus, incus, stapes

Question 17

muscle that tenses tympanic membrane and reduces amplitude of its oscillations?

Answer 17

tensor tympani mm

• this reduces damage to the internal ear when esposed to loud sounds.

Question 18

tensor tympani mm innervated by:

Answer 18

CN V3

Question 19

muscle that reduces oscillatory range of the stapes?

Answer 19

stapedius mm

Question 20

stapedius mm is innervated by:

Answer 20

CN VII

Question 21

internal ear

contains?

located?

component?

Answer 21

• contains the vestibulochoclear organ (hearing and balance)
• located in the petrous portion of TB
• components: bony labyrinth (cochlea, vestibule, and semicircular canals(

Question 22

cochlea

Answer 22

shell-shaped part of the bony labyrinth that contains the cochlear duct (concerned with hearing)

Question 23

Vestibule

Answer 23

small oval chamber containing the utricle and saccule (parts of the balance apparatus)

Question 24

Semicircular canals

Answer 24

communicate with the vestibule and house the semicircular ducts (concerned with balance)

Question 25

*internal ear