ear structure and development

Question 1

what do the outer (and outer layer of TM), middle (and inner layer of TM), inner ear develop from?

Answer 1

first pharyngeal groove, first pharyngeal pouch, otic placode

Question 2

what parts of temporal bone undergo intramembranous ossification and from where?

Answer 2

squamous and tympanic from first arch

Question 3

malleus and incus undergo what ossification and from where

Answer 3

endochondral from first arch

Question 4

stapes and styloid: ossification and where

Answer 4

endochondral from second arch

Question 5

petrous and mastoid: ossificationa nd where

Answer 5

endochondral from occipital somite

Question 6

muscles of middle ear. Fxn?

Answer 6

tensor tympani (malleus) and stapedius (stapes). Dampen ossicle vibration

Question 7

otic placode becomes___ then___

Answer 7

otic cyst, inner ear (cochlea, sc canals)

Question 8

first pharyngeal pouch becomes

Answer 8

auditory tube, middle ear, mastoid air cells

Question 9

middle ear: roof, floor, anterior, posterior

Answer 9

tegmen tympani (of petrous), jugular bulb, internal carotid and audtory tube, facial nerve and mastiod air cells

Question 10

ear ache is sensed by what nerve

Answer 10

tympanic branch of glossopharyngeal

Question 11

chorda tympani

Answer 11

branch of facial. taste to anterior 2/3 and salivary glands. found b/w maleus and incus

Question 12

external auditory meatus is innervated by

Answer 12

vagus