Ch 42: Ear Flashcards
The external ear consists of
auricle or pinna, the external auditory meatus (canal), and the tympanic membrane
The external auditory meatus connects the tympanic membrane to the exterior and is approximately
2.4 cm long
EAC ___ is cartilaginous and __ thirds bony
Outer 1/3
Inner 2/3
The tympanic membrane, which is made of multiple layers of____, separates the auditory canal from the middle ear
squamous epithelium
The middle ear houses the______ and opens into the eustachian tube to communicate with the pharynx
auditory ossicles, the tympanic cavity,
The middle ear cavity is lined with a mucoperiosteal membrane, and the eustachian tube is lined with_____ and has numerous mucous glands in the two-thirds of the tube closer to the pharynx
stratified columnar epithelium
The overall length of the eustachian tube is__
3.5 cm
The inner or internal ear lies in the petrous portion of the temporal bone and consists of
the bony labyrinth and the membranous labyrinth
Blood supply to the auricle and the external auditory canal comes from branches of the
posterior auricular artery and the superficial temporal artery, which arise from the external carotid artery
Blood is supplied to the middle ear region from branches of
ascending pharyngeal and middle meningeal arteries and from the artery of the pterygoid canal
The inner ear is supplied by the
internal auditory artery, which is a branch of the basilar artery, and from the anterior inferior cerebellar artery
The nerves innervating the ear include cranial nerves
V, VIII, IX, and X
T or F: The lymphatics in the middle ear and eustachian tube are rather sparse, and the inner ear has no lymphatics.
True
Arnold nerve is from CN __
CN X
Jacobsen nerve is from CN
IX
