Ear

Question 1

بسم الله الرحمن الرحيم
_________________
External ear formed of?

Answer 1

Aurcile
External auditory meatus
Tympanic membrane

Question 2

(Tympanic cavity)
It is an air filled space located in the …….
part of the temporal bone. It communicates
posteriorly with the ……….. &
anter.
with the …………..

Answer 2

Petrous temporal
__________
post = Mastoid air siuses
Ant = Auidtory eustichain tube

Question 3

irregular plate of elastic
cartilage, covered by skin in external ear ?

Answer 3

Auricle

Question 4

ceruminous glands
appears in ?
mention its strucute

Answer 4

External audiotry meatus
______________________
1/3 cartilage outer
2/3 bone inner
covered by skin + cerminuous glands

Question 5

Mention structure and function of Tympanic membrane

Answer 5

Formed of :
Oute epidemirs stratifed squamous epithleium
Inner Simple squamous or cuboidal
In between there is collagen and elastic fibers
___________________
Transmit sound waves to osicles of middle ear

Question 6

The wall of the auditory tube is usually
collapsed . Swallowing.
-It opens during

Answer 6

1-Swallowing
2-Yawning
3- Blowing of nose
releiving the pressure

Question 7

Bony osicles lined by
but middle ear cavity lined by?

Answer 7

Simple sqquamous
simple cubical

Question 8

Mention contents of middle ear

Answer 8

2 Windows :
Round and Oval window closed by membranes connecting the middle to inner ear
_______________________
3Osicles : Malleus ,incus , stapes
connecting the tympanic membrane to oval window
_________________________
2muscles :
Tensor tympani : connected to Malleus
Stapedius connected to stapes

Question 9

Mention functions of osicles

Answer 9

Magnification of Vibration received from tympanic membrane to reach properly to inner ear

Question 10

Mention fucntions of muscles found in middle ear

Answer 10

Loud noise casuing contratcion of these muscles that leads to limit movement of stapes + tympanic membrane to protect inner Ear

Question 11

Inner ear formed of ?

Answer 11

Auditory apparatus
Vestivular apparatus
- Bony labryinth + membranous labryinth

Question 12

Bony labryinth formed of ?

Answer 12

Series of spaces in temporal bone
Lined by ?endosteum
Filled with perilymph
_______________
formed of
Vestibule + semicirucular canals =Vestibualr
Choclea = auditory

Question 13

Membranous labryinth formed of ?

Answer 13

Ducts lining the bony labryinth
filled with endolymph Poor Na Rich K
Contains neuroepithelium for special sensory function
Formed of :
1-Saccule + utricle of vestibule
2-Semicircular ducts inside canals
Choclear duct

Question 14

The vestibule
It is the ……part of the
bony labyrinth.

Its lateral wall contains
…….+…?
It contains the membranous labyrinth :
…..+…..?

Answer 14

Central
________
ROund + Oval windows
__________
Saccule + utricle

Question 15

UTRICLE & SACCULE
*They are formed of…………+……………
*They are bound to the periosteum of the bony
vestibule by thin strands of ……………………..?
*They are connected to each other by the
??????????? duct.

Answer 15

Connective tissue + Simple squamous lining
___________________________________
Connective tissue containing blood vessels supplying membranous labryinth
Urticulosaccular duct

Question 16

How endolymatic sac formed and what is the function

Answer 16

Ducts of utricle + Saccule union fomring endolympahtic duct then endolymphatic sac for
1-Fomration of endolymph
2-Clearing debris from the endolymph by phagocytes

Question 17

Ductrs reunions connects

Answer 17

Saccule + Choclea

Question 18

Detecting the orientation of head inrelation to gravity + acceleration

Answer 18

Maculae
Macula of saccule
Maculea of utricle

Question 19

Mention strucute of Mauclea

Answer 19

Neuroepithelium =
Hair cells + supporting cells + Nerve endings

Question 20

Compare between type 1 and 2 hair cells Of macula

Answer 20

1: flask + cup free nerve ending surrounding the cell
2: columnar + many afferent free nerve endings

Question 21

Both 1 - 2 types of hair cells contains : ?

Answer 21

Kinocillium modified cilium with 9 dobulet no central singlets
Parallel to it Sterocilia the longest one is near Kinocillium
Many effernt nerve endings
Mitochondria + supranuclear golgi apparatus

Question 22

Describe supporting cells of Neuroepithelium of macula

Answer 22

Columnar with basal nuclei and microvilli apical with complexjunctions in between
Inbetween hair cells to support

Question 23

Mention function of Supporting cells of neuroepithelium of macukla

Answer 23

Nutrition of hair cells
Formation of Endolymph + Otolithic membrane

Question 24

Define otolithic membran

Answer 24

Gelatinous membran of glycoproteins and has otolithi or otoconia of calcium carrbonate on its surface

Question 25

*Function of the maculae:

Answer 25

Linear movement of head= displacement of endolymph =disturb the position of otolith = bending sterocilia= action potential = dendrite bipolar nerve cells inthe vestibulochoclear ganglion= veestibular part of vestibulochoclear nerve=brain stem and cerebellum

Question 26

*Semicircular canals Three long semicircular canals: superior, posterior & lateral. They arise and return to the vestibule , but two of them share an opening , so, there are 5 orifices not 6.

Answer 26

They are oriented at right angle to one another. -Each one is expanded at one end (ampulla). Its membranous labyrinth is called: the semicircular ducts, containing endolymph.

Question 27

-The receptor area is located in the ampulla of the semicircular ducts , and is called the ............? ( perpendicular to the long axis of the duct) .

Answer 27

Crista ampullaris

Question 28

How is the srtucute of crista ampullaris different from that of macula ?

Answer 28

The glycoprotein layer is called Cupula and there is no otolith

Question 29

Mention function of crista ampullaris

Answer 29

detect angular acceleration hrad rotation in 3d space casuing movment of endolymph and sterocilia causing impulses to vestibular part of Vestibulochoclear nerve

Question 30

*It is a hollow bony spiral tube. *It turns upon itself like a snail shell 2 ½ times around a central bony column (the modiolus).

Answer 30

choclea

Question 31

Osseus spiral lamina extends from ,,,, > traversing >?

Answer 31

Modioulus Traversing: 1-blood vessels 2-spiral ganglion 3-Choclear part of vestibulochoclear nerve

Question 32

chochlear duct separated from periolymhp by?

Answer 32

2membrane Vestibular and basilar membranes

Question 33

Vestibular membrane describe

Answer 33

ressiner's membrane Formed of 2 layers of squamous epithelium separated from each other by basment membrane it is the roof of choclear duct

Question 34

describe basilar membrane

Answer 34

floor of choclear duct extending from ossues spiral lamina a modilous to Spiral ligament at lateral wall supporting Organ of Corti

Question 35

*Above the vestibular membrane is called “the scala vestibuli *Below the basilar membrane is called “the scala tympani “ . *Both compartments communicate via an opening called the ........., near the apex of cochlea.

Answer 35

Helicotrema

Question 36

*Scala tympani communicates with the middle ear through the ???

Answer 36

round window

Question 37

Area of pseudostratidied epitehlium coveing the spiral ligmanet at lareal wall of choclear duct > ?

Answer 37

Stria Vascularis Contains intraepithelial pleux of capillaries

Question 38

characteristic ionic composition of endolymph due to ?

Answer 38

Stria vasuclaris ion transporting cells

Question 39

Covered by intradental cells ?

Answer 39

Spiral limbus

Question 40

Internal spiral tunnel covered by ?

Answer 40

Spiral limbus

Question 41

SPiral limbus is ?

Answer 41

Connective tissue coveing osseus spiral lamina bulging into the Salca media or Choclear duct

Question 42

Specialized receptor organ for hearing is?

Answer 42

Organ of Corti

Question 43

Site and compostiton of organ of corti >

Answer 43

Site basilar membrane of Choclear duct Strucute : formed of hair cells + supporting cells

Question 44

Compare between inner and oute hair cells of organ of corti

Answer 44

Inner : Flask shaped small One row of cells supported by inner phlangeal cells 50 apicl sterocillia Theri base synapses with afferents outer: COlumnar tall 3-4 rows supported by outer phlangeal celsl 100 apical sterocilia 3-4 rows supported by outer phlangeal cells their base synapse with afferent and efferents

Question 45

Tectorial membrane embedding the sterocilia of hair cells of organ of corti secreted by?

Answer 45

iNTRAdental cells covering spiral limbus

Question 46

Inner and oute pillar cells describe

Answer 46

they are tall cells with wide bases and narrow apices sepateted from each other by inner tunnel of corti but the apices are connected resting on basailar membrane

Question 47

Compare between outre and inner phalangeal cells of organ of corti

Answer 47

Outer surrounds the outer hair cells by theri cup shaped apices , with phalangeal process to surface and the uncovered surface of Outer hari cells contains fluid called space of Nuel Inner : Surrounds the inner hair cells completely

Question 48

Demarcate the inner border of organ of corti ? Demarcate the outer border of organ of corti. ? Lie lateral to cell of Hensen, resting on the underlying cells of Böettcher?

Answer 48

Bordere cells Hensesn cells Claiuds cells

Question 49

Explain mechamism of hearing

Answer 49

Sound reaches the external ear to be collected to pass in external auditory meatus till tympanic membrane causing osicles movemnts in specfice frequencies to oval window casuing movement of fluid in inner ear in cochlear duct casuing movement of sterocilia causing impulses and action potential to be discharge to brain *High frequencies are detected at the basal end of the membrane . ( narrowest basilar membrane with greater stiffness). *Low frequencies are detected at the apex.

Question 50

Conductive deafness

Answer 50

Occurs due to prevention of sound wave to pass from external ear to middle ear to organ of corti

Question 51

Conductive deafness

Answer 51

Occurs due to prevention of sound wave to pass from external ear to middle ear to organ of corti due to foreign body . otitis media , osteosclerosis fixation of footplates of stapes into oval window

Question 52

الحمدلله رب العالمين