Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Neuro Exam 3 > Ear anatomy and embryology > Flashcards

Ear anatomy and embryology Flashcards

(65 cards)

Start Studying
1
Q

what is the function of the auricle?

A

collect airwaves and funnel them into external acoustic meatus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the auricle made up of (structure)

A

cartilages
depressions (concha and schaphoid)
lobule –> composed of fibroelastic tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the blood supply to the auricle

A

posterior auricle artery and vein

superficial temporal artery and vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the innervation to the auricle

A

greater auricular (C2, C3) and lesser occipital

auriculotemporal
facial n
vagus n.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the lymphatic drainage of the auricle

A

mastoid, parotid lymph nodes –> deep cervical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the external acoustic meatus

what bone is it in
what is it lined with
what is the lateral 1/3 and the medial 2/3 made up of

A
  1. Canal traveling through tympanic portion of temporal bone to tympanic membrane.
  2. Canal traveling through tympanic portion of temporal bone to tympanic membrane.
  3. Lined by stratified squamous epithelium containing numerous ceruminous glands.
  4. Lateral 1/3 is cartilaginous; medial 2/3 is bony
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the blood supply to the external acoustic meatus (3)

A

a. Posterior auricular a. and v.
b. Superficial temporal a. and v.
c. Deep auricular a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the innervation of the external acoustic meatus

A

auricular temporal nerve (V3)

vagus n.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the lymphatic drainage of the external acoustic meatus

A

deep cervical lymph nodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is otitis external

A

inflammation of the external ear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the tympanic membrane attached to

A

handle of malleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the function of the tympanic membrane

A

convert sound waves into vibrations of middle ear ossicles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what does the tympanic membrane separate?
what is it covered with externally
and what covers it internally
which direction is the TM directed

A

a. Semitransparent, fibroelastic membrane
b. Separates external and middle ear.
c. Covered by epidermis externally; mucus membrane internally.
d. The membrane is directed anteriorly and inferiorly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the umbo

A

central concavity of the TM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the pars flaccida and pars tensa

A

b. Pars flaccida – superior, thin-walled portion

c. Pars tensa – inferior, thick-walled portion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the blood supply to external TM

what is the innervation to the external TM

A

blood–> deep auricular branch of maxillary

GSA –> auriculotemporal nerve
Vagus n.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the blood supply to the internal TM?

what is the innervation to the internal TM

A

blood_–> anterior tympanic off maxillary

innervation–> GVA tympanic branch of glossopharyngeal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

why is the TM a source of the cough reflex?

A

b/c of CN V being touched on the external surface of the TM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what arches is the auricle derived from

A

first and second pharyngeal arches.

6 auricular hillocks will later fuse to form the definitive auricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

defects of the auricle are commonly associated with what else?

A

chromosomal syndromes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is the external auditory meatus formed from

what is the meatal plug and what is its fate

what is a clinical correlation of the meatal plug

A

first pharyngeal cleft

b. Meatal plug forms from proliferation of epithelial cells; by 7th month degenerates.
c. CLINICAL CORRELATION: Persistence of meatal plug can cause deafness.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

external epithelium of tympanic membrane is derived from what

A

ectoderm of first pharyngeal cleft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

middle CT of TM is derived from what

A

mesoderm of first pharyngeal arch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

internal epithelium of TM is derived from what

A

endoderm of the first pharyngeal POUCH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what is in the middle ear
tympanic cavity--> mucous membrane-lined space within portion of the temporal bone and auditory ossicles
26
what is the function of the middle ear
1. Transfer of sound waves from gas to liquid medium (from external to internal ear). 2. Amplification of sound waves via vibration of bony ossicles. 3. Protective response to loud sounds (via tensor tympani & stapedius mm).
27
what is the roof of the tympanic cavity | what does it separate
tegmen tympani --> separates epitympanic recess from middle cranial fossa
28
floor of tympanic cavity | what does it separate
segment of temporal bone separating middle ear from internal jugular vein
29
what is the lateral wall of the tympanic cavity
tympanic membrane
30
what is the medial wall of the tympanic cavity what are the components
bony wall separating middle from internal ear promontory oval window round window
31
what is the promontory
mound of bone created by cochlea
32
what is the oval window
fenestra vestibule superior to the round window opens to vestibule of internal ear contacted by the stapes transmits motion of stapes to fluid of internal ear
33
what is the round window (fenestra cochlea)
opens to scala tympani covered with a thin membrane acts as a pressure release valve for fluids of the internal ear
34
what is the aditus ad antrum
entrance to the mastoid antrum
35
what is the posterior wall of the tympanic cavity
temporal bone aditus ad antrum facial canal
36
what is mastoiditis | and why is it clincally significant
middle ear infections can sometimes spread to the mastoid air cells via the aditus ad antrum (opening to these air cells)
37
what is the anterior wall of the tympanic cavity what openings are in it
segment of temporal bone separating middle ear from carotid canal opening for pharyngotympanic tube (aka auditory tube) and semi-canal (passage of tensor tympani).
38
what is the pharyngotympanic tube ``` what is it lined by what does it connect what is its function posterolateral third is made by what anteromedial 2/3s ``` what muscle can open this tube and what is its innervation
auditory tube 1. Mucous-membrane lined tube connecting middle ear and nasopharynx. 2. Function – balances pressure on external and internal sides of tympanic membrane. 3. Posterolateral third is bony; anteromedial 2/3 is cartilaginous. 4. Tensor veli palatini muscle can open the membranous tube (CN V3
39
what are the auditory ossicles
malleus incus stapes
40
malleus
contacts TM creates umbo vibrates in response to movment of the TM
41
incus
body articulates with head of malleus long limb articulates with stapes
42
stapes
base--> contacts oval window vibration of stapes induces motion of the fluid within the cochlear duct
43
what are the 2 muscles of the middle ear
stapedius | tensory tympani
44
stapedius attachments function innervation
a. Origin – posterior wall of tympanic cavity (pyramidal eminence) b. Insertion – stapes c. Function – dampens movements of ossicles d. Innervation – facial nerve (CN VII; SVE)
45
tensor tympani attachments function innervation
a. Origin – cartilaginous part of pharyngotympanic tube b. Insertion – malleus c. Function – dampens movements of ossicles d. Innervation – trigeminal nerve (V3; SVE) contracts when we are chewing or speaking
46
what is the cause of hyperacusis
paralysis of middle ear muscles can can this excessive hearing acuteness due to loss of dampening
47
what is the blood supply to the middle ear? *5 veins?
1. Inferior tympanic a (from ascending pharyngeal a) 2. Anterior tympanic a ( 2nd branch from maxillary a) 3. Posterior tympanic a (from stylomastoid a.) 4. Superior tympanic (from middle meningeal a.) 5. Artery of pterygoid canal (tubal branches to pharyngotympanic tube). 6. Venous drainage to ptergyoid plexus
48
what type of joints are the ossicles?
synovial | as we age they can undergo oto sclerosis and these can fuse! so we have shit hearing
49
what are the two nerves of the middle ear?
CN IX | CN VII
50
what are the three branches given off by CN VII
``` nerve to stapedius (SVE) greater petrosal (GVE-P ) chorda tympani (SVA and GVE-P) ```
51
what are the branches given off by CN IX in the middle ear?
tympanic branch (GVA, GVE-P) turns into lesser petrosal --> parotid gland
52
otitis media
inflammation of the middle ear--> often due to spread of infection from pharynx via pharyngo tympanic tube
53
what are the tympanic cavity and the auditory derived from
first pharyngeal pouch
54
malleus, incus and tensor tympani are derived from what
first pharyngeal arch
55
stapes and stapedius muscle are derived from wha
2nd pharyngeal arch
56
what is clinically significant about the stapes and its connection to the oval window
if it becomes congenitally ossified then deafness will ensue conductive hearing loss
57
where is the internal ear? | what does it contain
housed in the petrous portion of the temporal bone internal ear contains the vestibulocochlear organ involved in balance and hearing
58
what is inside the bony labyrinth
perilymph cochlea vestibule semicircular canals
59
what is inside the membranous labyrinth
endolymph all portions innervated by CN VIII
60
what is the endolymphatic duct
maintains the volume and composition of endolymphatic fluid must have high K concentration
61
what is the cochlear duct
organ of hearing vestibular membrane- roof basilar membrane - floor spiral organ of corti - hair cells
62
what are the two components of the vestibulocochlear nerve (CNVIII)
3. Vestibular portion innervates semicircular ducts, utricle, and saccule to carry proprioceptive information (movements of the head) to the brain. 4. Cochlear portion innervates cochlear duct to carry information about sound to the brainstem (spiral organ)
63
what is the membranous labyrinth derived form
otic placode --> otic sac--> otic vesicle
64
what is the path of production of sound
1. Airways travel down external acoustic meatus causing vibration of tympanic membrane. 2. Motion of the tympanic membrane causes vibration of the three middle ear ossicles. 3. Footplate of stapes contacts oval window and causes movement of the fluid in the inner ear. 4. Movement of fluid in the cochlear duct causes bending of the hair cells imbedded within the spiral organ. 5. Bending of these hair cells initiates signaling events which ultimately lead to propagation of a nerve impulse along the cochlear portion of CN VIII.
65
what is bony labyrinth derived from?
surrounding mesenchyme (vestibule, semicirucular canals, cochlea)

Neuro Exam 3 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions