Bns 1 Exam- Foster/ear

Front 1

When is the inner ear arises?

Back 1

24th-28th day from ectoderm,
invaginating into the developing head and coordinating its structure with the 1st two branchial arches.

Front 2

The ear developments in three largely separate parts, are:

Back 2

External ear
Middle ear
Internal ear

Front 3

Most of the ear structures are associated with ____1__ and ___2______with no direct origin from ___3__________

Back 3

1. ectoderm
2. branchial arches
3. neuroectoderm.

Front 4

The inner ear develops from what vesicle?

Back 4

as a small ectodermal vesicle, the otic vesicle.

Front 5

The inner ear develops from what cells?

Back 5

mostly out of neural crest mesenchymal cells.

Front 6

The nerve to the inner ear develops from what?

Back 6

from adjacent ectoderm, in a similar manner to neural crest.

Front 7

What day is the otic pit develops?

Back 7

25th day

Front 8

What forms the otic pit?

Back 8

The Otic placode cells invaginate into the mesoderm to form an otic pit.

Front 9

When is the otic vesicle develops?

Back 9

28th day

Front 10

What cells will form Cn 8?

Back 10

Neural placode cells will form CN VIII

Front 11

Everything that lines the cochlear duct (scala media) origin from what?

Back 11

otic vesicle origin.

Front 12

Middle and external ear develop from what region?

Back 12

the pharyngeal region.

Front 13

External ear comes from what branchial arches ?

Back 13

1 (tragus and anterior helix) and branchial arch 2 (antitragus and posterior helix).

Front 14

External auditory meatus and canal comes what branchial arches?

Back 14

External auditory meatus and canal comes from 1st branchial groove.

Front 15

Middle ear comes from what?

Back 15

1st pharyngeal pouch.

Front 16

2 major functions of internal ear?

Back 16

Transmits proprioceptive information to the brain via the vestibular division of CN VIII regarding the position and movement of the head (equilibrium and balance) *


Transmits auditory information to the brain via the cochlear division of CN VIII regarding the sense of hearing.
Both mechanoreceptors, closely related

Front 17

Where is the internal ear located?

Back 17

located in petrous part of temporal bone

Front 18

parts of internal ear

Back 18

bony labyrinth and membranous labyrinth

Front 19

bony labyrinth:

Back 19

series of cavities located within petrous part of temporal bone  contain clear fluid (perilymph) in which membranous labyrinth is suspended
perilymph closely resembles CSF (rich in Na and poor in K)

Front 20

Parts of the bony labyrinth

Back 20

vestibule, semicircular canals and cochlea

Front 21

perilymph closely resembles what and where is it located?

Back 21

closely resembles to CSF (rich in Na and poor in K) and located in the bony labyrinth in the internal ear

Front 22

Cochlea consists of what?

Back 22

consists of central pillar (modiolus) around which a hollow bony tube makes 2¾ spiral turns - each successive turn is of a smaller radius (conical shape)

Front 23

Cochlea resembles what?

Back 23

resembles a snail shell

Front 24

What is the membranous labyrinth?

Back 24

- interconnected membranous sacs and tubes located within bony labyrinth
-filled with endolymph and surrounded by perilymph
-endolymph resembles intracellular fluid (rich in K and poor in Na)

Front 25

Where is endolymph located and resembles what?

Back 25

in membranous labyrinth and resembles intracellular fluid (rich in K and poor in Na)

Front 26

membranous labyrinth:
consists of:

Back 26

cochlear duct (scala media)  located within bony cochlea  contains receptors for hearing
semicircular ducts (located within semicircular canals)
utricle and saccule (located within vestibule)
semicircular ducts, utricle and saccule contain vestibular receptors

Front 27

The three sensory areas of the membranous labirinth are

Back 27

1. Three crista ampullaris of the semicircular canals.
2. Macula of utricle and Macula of saccule.
3. Organ of Corti of the cochlea.

Front 28

What is the function of The maculae of the utricle and saccule?

Back 28

receive and transmit information to the CNS on the position of the head in space.

Front 29

What is the function of The three crista ampullaris of the semicircular canals

Back 29

receive & transmit information to the CNS on the direction of movement of the head.

Front 30

What is the function of The organ of Corti of the cochlea?

Back 30

receives & transmits information of sound (hearing) to the CNS.

Front 31

What is it?
__________of the semicircular canals are saddle-shaped structures which extend into the lumen of the membranous labyrinth.

Back 31

Cristae Ampullaris:

Front 32

consist of a flattened sheet of neuroepithelial cells covered by an otolithic membrane, a gelatinous glycoprotein layer containing crystals of calcium carbonate (otolith or otoconia).

Back 32

The maculae of the saccule and utricle

Front 33

Cristae Ampullaris
are similarly covered by a layer of gelatinous glycoprotein called a ______

Back 33

cupula (cup-shaped). *

Front 34

What are the 2 cell types of the cristae and maculae?

Back 34

1. hair (receptor) cells - columnar cells which have a tuft of non-motile stereocilia and a single non-motile cilium (kinocilium) at the free (apical) surface.
2. supporting cells - tall columnar cells each containing a basally located nucleus and apically located microvilli.

Front 35

What terminate on the basolateral surfaces of hair cells.?

Back 35

Processes from bipolar neurons, whose cell bodies are located in the vestibular ganglia

Front 36

What are the Two types of hair cells?

Back 36

Type 1 hair cells and Type 2 hair cells (who would thought ;-P )

Front 37

What hair cell type is this?
flask-shaped cells, surrounded by a cup-shaped afferent nerve ending called a calyx or chalice.

Back 37

type 1

Front 38

rod-shaped cells, smaller afferent and efferent nerve endings.

Back 38

type 2

Front 39

Functional aspects of hair cells depens on what 3 things?

Back 39

1. Arrangement of stereocilia
2. Resting hair cells
3. depolarized hair cells

Front 40

Overview of Auditory System
hearing apparatus is a complex ____1______
and it converts ___2___ waves into _____3_____

Back 40

1. transducer
2. sound waves
3. coded AP

Front 41

A cross-section of any turn of cochlea shows 3 fluid-filled compartments (wind together in spiral pattern around modiolus):
What are these compartments?

Back 41

1. scala media (cochlear duct)
2. scala vestibuli
3. scala tympani

Front 42

What contains perilymph?

Back 42

scala vestibuli and scala tympani contain

Front 43

Where scala vestibuli and scala tympani continuous with each other?

Back 43

apex of cochlea (helicotrema)

Front 44

cochlear duct is part of what?

Back 44

membranous labyrinth

Front 45

scala vestibuli communicates with ____1___ at base of cochlea and with _____2____at apex of cochlea (helicotrema)

Back 45

1. vestibule
2. scala tympani

Front 46

scala tympani spirals from apex to base of cochlea communicates with ___1.____ via the _______

Back 46

communicates with
1. tympanic cavity via
2. round window (closed by secondary tympanic membrane)

Front 47

The three sensory areas of the membranous labirinth are

Back 47

1. Three crista ampullaris of the semicircular canals.
2. Macula of utricle and Macula of saccule.
3. Organ of Corti of the cochlea.

Front 48

What is the function of The maculae of the utricle and saccule?

Back 48

receive and transmit information to the CNS on the POSITION of the head in space.

Front 49

What is the function of The three crista ampullaris of the semicircular canals

Back 49

receive & transmit information to the CNS on the DIRECTION of movement of the head.

Front 50

What is the function of The organ of Corti of the cochlea?

Back 50

receives & transmits information of sound (hearing) to the CNS.

Front 51

What is it?
__________of the semicircular canals are saddle-shaped structures which extend into the lumen of the membranous labyrinth.

Back 51

Cristae Ampullaris:

Front 52

consist of a flattened sheet of neuroepithelial cells covered by an otolithic membrane, a gelatinous glycoprotein layer containing crystals of calcium carbonate (otolith or otoconia).

Back 52

The maculae of the saccule and utricle

Front 53

Cristae Ampullaris
are similarly covered by a layer of gelatinous glycoprotein called a ______

Back 53

cupula (cup-shaped). *

Front 54

What are the 2 cell types of the cristae and maculae?

Back 54

1. hair (receptor) cells - columnar cells which have a tuft of non-motile stereocilia and a single non-motile cilium (kinocilium) at the free (apical) surface.
2. supporting cells - tall columnar cells each containing a basally located nucleus and apically located microvilli.

Front 55

What terminate on the basolateral surfaces of hair cells.?

Back 55

Processes from bipolar neurons, whose cell bodies are located in the vestibular ganglia

Front 56

Scala Media (Cochlear Duct) is what kind of a shape in cross section?

Back 56

triangular

Front 57

Scala Media (Cochlear Duct)
is separated from scala tympani by __________

Back 57

basilar membrane

Front 58

Scala Media (Cochlear Duct)
is separated from scala vestibuli by _________

Back 58

vestibular (Reissner’s) membrane

Front 59

Where is stria vascularis located?

Back 59

lateral wall of cochlear duct

Front 60

What does stria vascularis produce?

Back 60

produces most of the endolymph of the membranous labyrinth

Front 61

T/F
stria vascularis highly vascular and slightly pigmented structure

Back 61

True
THIS IS THE ONLY EXCEPTION! Epithelial cells are not vasular!

Front 62

Where is the auditory receptor located?

Back 62

spiral organ (of Corti) on the basilar membrane

Front 63

What cells the auditory receptor have and what do you find on these cells?

Back 63

neuroepithelial receptor cells and supporting cells and on the neuroepithelial cells you find hair cells (stereocilia project from free surface of cells)

Front 64

hair cells arranged in 2 groups on the spiral organ of corti. What are those?

Back 64

inner and outer hail cells

Front 65

Baby vomits milk when fed and has a gastric bubble.

Back 65

tracheosophageal fistula

Front 66

These hair cells increase from 3 rows at base of cochlea to 5 rows at apex

Back 66

outer hail cells

Front 67

Cochlear hair cells bear only ___1_____and no ___2___ on their free apical surfaces.

Back 67

1. stereocilia
2. kinocilia

Front 68

What do you find in the organ of corti?

Back 68

complex epithelial structure which contains the site of sound reception, the inner and outer hair cells.

Front 69

What is the tectorial membrane ?

Back 69

Overlying the hair cells in the organ of corti is a glycoprotein-rich structure, the tectorial membrane that makes contact with the stereocilia of the hair cells.

Front 70

Fill in the blank.
When stereocilia become __1___ , the longest stereocilium is located on -the _____2___ moves inward, stereocilia become ___3___

Back 70

1. polarized
2. outer part of cell
3. shorter

Front 71

Outward deflection of stereocilia (toward longest stereocilium or toward stria vascularis) causes _______ of the hair cell

Back 71

depolarization

Front 72

Inward deflection of stereocilia causes ________ of the hair cell

Back 72

hyperpolarization

Front 73

In the Spiral Organ (of Corti)
vibrations reaching base of stapes are transferred to What?

Back 73

perilymph of scala vestibuli

Front 74

when footplate of stapes moves in, secondary tympanic membrane bulges what way/direction?

Back 74

out

Front 75

when footplate of stapes moves out, secondary tympanic membrane is drawn what way?

Back 75

inward

Front 76

In Spiral Organ (of Corti)
if cochlear duct had rigid walls, waves would have to pass entire length of __1___and return through __2___ to round window

Back 76

1, scala vestibuli
2. scala tympani

Front 77

In Spiral Organ (of Corti)
walls of cochlear duct are flexible so displacement of perilymph by movement of stapes causes deflection of ______ membrane.

Back 77

basilar

Front 78

What is tonotopic representation?

Back 78

Spiral Organ (of Corti)
sounds of different frequencies cause waves in basilar membrane with maximal amplitude (maximal membrane displacement) at different points along membrane 

Front 79

In Spiral Organ (of Corti)
high frequency sounds cause waves of maximal amplitude close to _____of cochlea

Back 79

base

Front 80

In Spiral Organ (of Corti)
low frequency sounds cause waves of maximal amplitude close to _____ of cochlea

Back 80

apex

Front 81

hair cells are very sensitive transducers. It convert mechanical force applied to _________ into electrical signal

Back 81

stereocilia

Front 82

Upward movement of basilar membrane causes stereocilia deflected ___1____ this tension causes opening of mechanically gated ___2___-channels and __3___enters cell which causes __4___ of hair cell

Back 82

1. outward (toward stria vascularis)
2. ion channels (selective to K)
3. K
4. depolarization

Front 83

IN Mechanoelectrical Transduction depolarization opens __1____channels the __2__ enters cell and further depolarization and increased intracellular __3__ will lead to binding of ___4____vesicles to cell membrane and release of ___5__ into synaptic cleft between hair cell and ____6____ nerve (afferent) fiber lead to depolarization of afferent fiber and ___7____transmitted along ___8____ nerve fibers

Back 83

1. voltage-sensitive Ca
2-3. Ca
4. glutamate-containing
5. glutamate
6. cochlear
7. action potential
8. cochlear

Front 84

where is the cell bodies of sensory neurons in the cochlea and what they form?

Back 84

sensory neurons' of CB's form spiral ganglion, which is located within modiolus

Front 85

What kind of sensory neurons are in the cochlea?

Back 85

bipolar neurons

Front 86

what form cochlear division of vestibulocochlear nerve (CN VIII)?

Back 86

central processes of sensory neurons of spiral ganglion

Front 87

cochlear nerve also contains efferent fibers from ___?

Back 87

the superior olivary nucleus (in lower pons)

Front 88

What is the functional role of efferent system in hearing ?

Back 88

not well known.
It has been suggested that it may be involved in selectively tuning cochlea to important sounds