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Flashcards in Ear anatomy and physiology Deck (69):
1

What bone contains everything to do with the ear?

Temporal

2

What are the three anatomical divisions of the ear?

External
Middle
Internal

3

What functions does the ear play?

Hearing and balance

4

Where are the temporal bones found?

Lateral side of head
Inferior to parietal bone and posterior to sphenoid bone

5

Name four important lateral parts of the temporal bone

Styloid process
External auditory meatus
Mastoid process
Zygomatic process

6

What links the temporal bone with the zygomatic bone?

Zygomatic process of temporal bone and temporal process of zygomatic bone

7

Name three important parts on the inferior temporal bone

Mandibular fossa
Stylomastoid foramen
Extracranial opening into carotid canal

8

Name an important opening in the internal part of the temporal bone

Internal acoustic meatus

9

What passes through the stylomastoid foramen?

CNVII

10

Where does CNVII pass?

Stylomastoid foramen

11

What foramen is found between the temporal and occipital bones?

Jugular foramen

12

What passes through the internal acoustic meatus?

CNVII
CNVIII
Labyrinthine artery and vein

13

What does CNVII (facial) do?

Motor to face and stapedius
Ant 2/3 of taste
Secretory to lacrimal and salivary glands
General sensation to external ear

14

What does CNVIII (vestibulococlear) do?

Special sense from ear

15

Where does the labyrinthine artery arise from?

Circle of Willis

16

What is the job of the external ear?

To collect sound

17

What is the job of the middle ear?

To amplify sound

18

What if is the job of the inner ear?

To create sensory signals

19

What nerves supply sensory to the majority of the pinna?

Spinal nerves C2+3

20

What cranial nerves supply sensory to the external ear?

V3. VII and X

21

Where in the external ear does V3 supply?

Most of superior around tragus and head.
Superior EAM and most of tympanic membrane

22

Where in the external ear does VII supply?

A smattering in concha

23

Where in the external ear does X supply?

Concha
Inferior EAM and part of tympanic membrane

24

Describe the lymphatic drainage of the external ear

Superior lateral- parotid
Superior cranial- Mastoid
Rest- superficial cervical

25

Where do all the lymph nodes of the head eventually drain?

Deep cervical lymph nodes

26

What are the four important parts of the tympanic membrane?

Pars flaccida- Thinnest part and most superior
Pars tensa- Most of it and inferior
Cone of light- Anterior
Umbo- Part of malleus and slopes posterior

27

How can you tell the orientation of an ear from the tympanic membrane?

Umbo slopes backwards and cone of light anterior.

28

Which nerve supplies sense to the middle ear and eustachian tubes?

CNIX (glossopharyngeal)

29

What are the three bones of the middle ear?

Malleus
Incus
Stapes

30

What two muscles are found in the middle ear?

Tensor tympani
Stapedius

31

What kind of joint links the ossicles?

Synovial

32

What is the superior part of the middle ear called?

Epitympanic recess

33

What links the inner ear with the nasal cavity?

Eustation tubes

34

What links the middle ear with the inner ear?

Oval and round windows

35

What two nerves pass through the middle ear?

CNVII
Chorda tympani

36

What is the chorda tympani a branch of?

CNVII

37

is CNVII or the chorda tympani more lateral?

Chorda tympani

38

Describe the route of CNVII

Exit cranium via eternal acoustic meatus
Enter then leave middle ear in facial canal of middle ear
Leaves temporal bone vie stylomastoid foramen

39

Where does the Eustachian tube enter the pharynx?

Nasopharynx inferior to adenoids

40

What nerve supplies the naso/oropharynx, Eustachian tubes and middle ear?

CNIX (glossopharyngeal)

41

What does the stapedius muscle do?

Reduces movement to protect inner ear from loud noises

42

What does the chorda tympani do?

Ant 2/3 taste
Submandibular and lingual salivary glands

43

What are the muscles of facial expression (4 of them)?

Frontalis
Orbicularis oculi
Elevator of lips
orbicularis oris

44

How do you test the muscles of facial expression?

Frontalis- Frown
Orbicularis oculi- Close eyes tight
Elevator of lips- Smile
orbicularis oris- Maintain puffed out cheeks

45

What bony structure contains the inner ear?

Otic capsule

46

What fluid is found in the otic capsule?

Perilymph

47

What floats in the perilymph?

Membranous labyrinth

48

What is contained in the Membranous labyrinth?

Endolymph

49

Which is more superior the round or oval window?

Oval

50

What three parts are there to the labyrinths?

Cochlear ducts
Semicircular ducts
Utricles and saccules

51

What parts make up the vestibular system?

Semicircular ducts
Utricles and saccules

52

What do Utricles and saccules do?

sense lineal movement

53

What do semicircular ducts do?

Sense angular movement

54

What is found at the entrance to all semicircular canals?

Ampula

55

How many semicircular canals do we have?

3 each side

56

What are the three compartments of the cochlear apparatus?

Scala media
Scala vestibuli
Scala tympani

57

Where is perilymph found?

Scala vestibuli and tympani

58

Where is endolymph found?

Scala media

59

What is found in the scala media?

Basilar membrane

60

Where does the vestibulocochlear (CNVIII) enter the skull?

Internal acoustic meatus

61

Where does CNVIII join the brain stem?

Pontomedullary junction

62

How does the ear sense sound?

vibrations pass through the oval window into the scala vestibuli.
Pass along here vibrating the basilar membrane activating the organ of Corti.
Different parts of the BM detect different frequencies etc
Vibration passes out via round window.

63

What are the three semicircular canals called?

Horizontal- Flat. Apex lateral
Superior- Going up. Apex superior
Posterior- Going back. Apex posterior

64

Where are hair cells in the semicircular canals found?

Ampula

65

What provides a reference for the stereocilia/hair cells in the ampulla?

Kinocilium

66

How do the saccules and utricles sense linear movement?

Otolith crystals bend the cilia causing depolarisation.

67

What cell type lines the external auditory canal?

Stratified epithelium- skin

68

What special glands are found in the skin of the ear?

Sebaceous and ceruminous- produce earwax

69

What cell type is found in the middle ear?

Columnar lines mucosa