Histology of the Ear Flashcards
(71 cards)
1
Q
the middle ear is on the ____ side of the tympanic membrane
A
medial
2
Q
How is the middle ear connected to the nasal cavity?
A
by the auditory/eustachian tube
3
Q
The middle ear contains what three bones?
A
malleus, incus, and stapes
4
Q
the foot of the stapes sits on the ___ ____
A
oval window
5
Q
the external and middle ear are filled with what?
A
air
6
Q
The inner ear is embedded in the bone of the ___ ___ of the ____ bone
A
The inner ear is embedded in the bone of the petrous pyramidof the temporal bone
7
Q
The inner ear contains the ____ canals, _____, and _____. It also contains Cranial Nerve _____.
A
The inner ear contains the semicircular canals, vestibule and cochlea. It also contains Cranial Nerve VIII.
8
Q
The internal ear transmits _____ information to the brain via the _____ division of ______ regarding the ____ and _____ of the ____ (equilibrium)
A
The internal ear transmits proprioceptive information to the brain via the vestibular division of CN VIII regarding the position and movement of the head (equilibrium)
9
Q
The internal ear transmits ____ information to the brain via the _____ division of _____ regarding the sense of _____.
A
The internal ear transmits auditory information to the brain via the cochlear division of CN VIII regarding the sense of hearing.
10
Q
The two parts of the internal ear are the _____ labyrinth and the ____ labyrinth
A
The two parts of the internal ear are the bony labyrinth and the membranous labyrinth
11
Q
Bony Labyrinth:
- Series of _____ located within ____ part of ____bone and contain____ fluid (____) in which _____ ______ is suspended
- Parts: _____, ______ canals and ______
A
Bony Labyrinth:
- Series of cavities located within petrous part of temporal bone and contain clear fluid (perilymph) in which membranous labyrinth is suspended
- Parts: vestibule, semicircular canals and cochlea
12
Q
______closely resembles CSF (rich in ____ and poor in ____)
A
Perilymph closely resembles CSF (rich in Na+ and poor in K+)
13
Q
The superior, posterior, and lateral loops of the semicircular canals are ______ to each other in order to detect all planes of movement.
A
The superior, posterior, and lateral loops of the semicircular canals are perpendicular to each other in order to detect all planes of movement.
14
Q
The semicircular canals are connected to the _____.
A
The semicircular canals are connected to the vestibule.
15
Q
The ____ window opens into the vestibule, while the ___ window leads out of the vestibule.
A
The oval window opens into the vestibule, while the round window leads out of the vestibule.
16
Q
inside semicircular canals: _____ ______
-contains own opening filled with ______
A
inside semicircular canals: semicircular ducts
-contains own opening filled with endolymph
17
Q
Membranous Labyrinth:
- Interconnected _____ ____ and ____ located within _____ _____
- Filled with ______and surrounded by _____
A
Membranous Labyrinth:
- Interconnected membranous sacs and tubes located within bony labyrinth
- Filled with endolymph and surrounded by perilymph
18
Q
_____ resembles intracellular fluid (rich in ___ and poor in ___)
A
Endolymph resembles intracellular fluid (rich in K+ and poor in Na+)
19
Q
endolymph is made by cells located within ____ _____
good for proper transduction of _____and _____ signals
A
endolymph is made by cells located within membranous labyrinth
good for proper transduction of hearing and vestibular signals
20
Q
Membranous Labyrinth Parts:
- ____ ____ (scala media) located within bony cochlea; contains _____ for hearing
- Semicircular ducts (located within ______)
- _____ and _____ (located within vestibule)
- Semicircular ducts, utricle and saccule contain _____ ______
A
Membranous Labyrinth Parts:
- 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
21
Q
the utricle is next to the ____ ____
A
semicircular ducts
22
Q
The saccule is attached to the ____ and the ___ _____
A
The saccule is attached to the utricle and the cochlear duct
23
Q
the _____ cell bodies of the cochlear nerve surround the ____ of the _____
A
the bipolar cell bodies of the cochlear nerve surround the spiral of the cochlea.
24
Q
Three sensory areas of the membranous labyrinth:
- Macula of ____ and macula of ____. *
- Three _____ _____ of the semicircular canals. *
- ____ of ____ of the ____.
A
Three sensory areas of the membranous labyrinth:
- Macula of utricle and macula of saccule. *
- Three crista ampullaris of the semicircular canals. *
- Organ of Corti of the cochlea.
25
The ______ of the utricle and saccule:
\_\_\_\_ and ____ information to the CNS on the\_\_\_\_ of the ____ in \_\_\_\_
The **_maculae_** of the utricle and saccule:
**_receive_** and **_transmit_** information to the CNS on the **_position_** of the **_head_** in **_space_**
26
The three ________ \_\_\_\_\_\_\_of the semicircular canals:
receive & transmit information to the CNS on the _____ of ______ of the head.
The three **_crista ampullaris_** of the semicircular canals:
receive & transmit information to the CNS on the **_direction_** of **_movement_** of the head.
27
Two Cell Types of the Cristae and Maculae:
1) \_\_\_(receptor) cells - \_\_\_\_cells which have a tuft of \_\_\_\_-\_\_\_\_ \_\_\_\_\_\_and a single \_\_\_\_-\_\_\_\_\_ \_\_\_\_\_(kinocilium) at the ____ (apical) surface.
2) ____ cells - ____ \_\_\_\_\_\_cells each containing a \_\_\_\_located _____ and \_\_\_\_\_located \_\_\_\_\_.
Two Cell Types of the Cristae and Maculae:
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_**.
28
Processes from _____ neurons, whose cell bodies are located in the _____ \_\_\_\_\_\_, terminate on the ____ surfaces of hair cells.
Processes from **_bipolar_** neurons, whose cell bodies are located in the **_vestibular_** **_ganglia_**, terminate on the **_basolateral_** surfaces of hair cells.
29
Two types of hair cells:
a) _____ hair cells: \_\_\_-shaped cells, surrounded by a cup-shaped afferent nerve ending called a \_\_\_\_or \_\_\_\_.
b) \_\_\_\_\_hair cells: \_\_\_\_-shaped cells, ____ afferent and ____ nerve endings.
Two types of hair cells:
a) **_Type I_** hair cells: **_flask_**-shaped cells, surrounded by a cup-shaped afferent nerve ending called a **_calyx_** or **_chalice_**.
b) **_Type II_** hair cells: **_rod-_**shaped cells, **_smaller_** afferent and **_efferent_** nerve endings.
30
The stereocilia of hair cells are arranged in \_\_\_\_
rows
31
\_\_\_\_ links individual stereocilia rows
filament
32
the _____ recess is where the utricle is found.
elliptical
33
the ___ recess is where the saccule is found.
spherical
34
the _____ region of the utricle has no hairs
nonsensory
35
The _____ of the saccule and utricle both consist of a flattened sheet of ______ cells covered by an _____ membrane, a gelatinous _____ layer containing crystals of _____ \_\_\_\_\_\_.
The **_maculae_** of the saccule and utricle both 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).
36
Cristae Ampullaris:
Located in the _____ \_\_\_\_\_\_ are \_\_\_\_-shaped structures which extend into the ____ of the _____ labyrinth.
Cristae Ampullaris:
Located in the **_semicircular canals_** are **_saddle_**-shaped structures which extend into the **_lumen_** of the **_membranous_** labyrinth.
37
cristae ampullaris are covered by a layer of gelatinous ______ called a \_\_\_\_\_
cristae ampullaris are covered by a layer of gelatinous **_glycoprotein_** called a **_cupula_** (cup-shaped).
38
endolymph drains through the _______ duct
endolymphatic duct
\*if this doesn't drain, it can cause vestibular AND hearing problems!
39
the perilymphatic duct drains into the ______ \_\_\_\_\_.
subarachnoid space
40
Scala vestibule communicates with the ____ \_\_\_\_ and surrounds the ____ \_\_\_\_\_.
Scala vestibule communicates with the **_oval window_** and surrounds the **_cochlear duct_**.
41
The scala tympani leads to the ____ \_\_\_\_\_.
round window
42
The cochlea consists of central pillar (\_\_\_\_\_) around which a hollow bony tube makes 2¾ spiral turns, and each successive turn is of a \_\_\_\_\_radius (\_\_\_\_ shape)
The cochlea consists of central pillar (**_modiolus_**) around which a hollow bony tube makes 2¾ spiral turns à each successive turn is of a **_smaller_** radius (**_conical_** shape)
43
Sound waves come through the \_\_\_\_\_ear and hit the _____ membrane, causing it to vibrate. The ____ will push on the \_\_\_\_window and cause fluid to go to the ____ \_\_\_\_\_. The fluid then goes back to the _____ \_\_\_\_\_\_ and escapes through the _____ window.
Sound waves come through the **_external_** ear and hit the **_tympanic_** membrane, causing it to vibrate. The **_stapes_** will push on the **_oval_** window and cause fluid to go to the s**_cala vestibuli_**. The fluid then goes back to the **_scala tympani_** and escapes through the **_round_** window.
44
The spiral ganglion contains the cell bodies of what cranial nerve?
CN VIII
45
What are the three fluid filled compartments of the cochlea?
scala media, scala vestibuli, scala tympani
46
The vestibular membrane separates the ____ \_\_\_\_\_from the ____ \_\_\_\_\_.
The **_vestibular_** membrane separates the **_scala vestibuli_** from the **_scala media_**.
47
The basilar membrane separates the ____ \_\_\_\_ from the ____ \_\_\_\_.
The **_basilar_** membrane separates the **_scala media_** from the **_scala tympani_**.
48
scala vestibuli and scala tympani contain _____ and are continuous with each other at _____ of cochlea (\_\_\_\_\_)
scala vestibuli and scala tympani contain **_perilymph_** and are continuous with each other at **_apex_** of cochlea (**_helicotrema_**)
49
cochlear duct is part of \_\_\_\_\_\_labyrinth
cochlear duct is part of **_membranous_** labyrinth
50
scala vestibuli communicates with ____ at base of cochlea and with ____ \_\_\_\_\_ at apex of cochlea (helicotrema) --\> scala _____ spirals from apex to base of cochlea --\> communicates with tympanic cavity via \_\_\_\_\_window (closed by secondary tympanic membrane)
scala vestibuli communicates with **_vestibule_** at base of cochlea and with **_scala tympani_** at apex of cochlea (helicotrema) --\> scala **_tympani_** spirals from apex to base of cochlea --\> communicates with tympanic cavity via **_round_** window (closed by secondary tympanic membrane)
51
\_\_\_\_ ______ lines the lateral wall of cochlear duct. It is a highly ____ and slightly _____ structure that produces most of the _____ of the ______ labyrinth.
**_stria vascularis_** lines the lateral wall of cochlear duct. It is a highly **_vascular_** and slightly **_pigmented_** structure that produces most of the **_endolymph_** of the **_membranous_** labyrinth.
52
The ____ \_\_ _____ of the cochlea receives & transmits information of \_\_\_\_\_(hearing) to the \_\_\_\_\_.
The **_organ of Corti_** of the cochlea receives & transmits information of **_sound_** (hearing) to the **_CNS_**.
53
The neuroepithelial \_\_\_\_\_cells of the organ of corti are \_\_\_\_\_cells.
The neuroepithelial **_receptor_** cells of the orga of corti are **_hair_** cells.
54
Hair cells arranged in 2 groups:
* \_\_\_\_\_ hair cells: form ____ \_\_\_\_\_ from base to apex of cochlea
* \_\_\_\_ hair cells: increase from ____ rows at \_\_\_\_\_of cochlea to \_\_\_\_rows at \_\_\_\_\_.
Hair cells arranged in 2 groups:
* **_Inner_** hair cells: form **_single row f_**rom base to apex of cochlea
* **_Outer_** hair cells: increase from **_3_** rows at **_base_** of cochlea to **_5_** rows at **_apex_**
55
Cochlear hair cells bear only _____ and no ______ on their free apical surfaces.
Cochlear hair cells bear only **_stereocilia_** and no **_kinocilia_** on their free apical surfaces.
56
_**\_\_\_\_\_**_ membrane: gelatinous arm that extends over _**\_\_\_\_\_**_ cells; tips of \_\_\_\_\_are embedded in (or brush) \_\_\_\_\_membrane
**_Tectorial_** membrane: gelatinous arm that extends over **_hair_** cells; tips of **_stereocilia_** are embedded in (or brush) **_tectorial_** membrane
57
Stereocilia are \_\_\_\_\_\_: longest stereocilium is located on _____ part of cell; as one moves \_\_\_, stereocilia become \_\_\_\_\_
Stereocilia are **_polarized_**: longest stereocilium is located on **_outer_** part of cell; as one moves **_inward_**, stereocilia become **_shorter_**
58
Outward deflection of stereocilia (toward ____ stereocilium or toward ___ \_\_\_\_\_\_\_ causes _____ of the hair cell
Outward deflection of stereocilia (toward **_longest_** stereocilium or toward **_stria vascularis_**) causes **_depolarization_** of the hair cell
59
Inward deflection of stereocilia causes _____ of the hair cell
**_Inward_** deflection of stereocilia causes **_hyperpolarization_** of the hair cell
60
* Vibrations reaching base of stapes are transferred to ____ of ____ \_\_\_\_\_\_
* When footplate of stapes moves in, secondary tympanic membrane ____ \_\_\_\_.
* When footplate of stapes moves out, secondary tympanic membrane is ____ \_\_\_\_
* Vibrations reaching base of **_stapes_** are transferred to **_perilymph_** of **_scala vestibuli_**
* When footplate of stapes moves in, secondary tympanic membrane **_bulges out_**
* When footplate of stapes moves out, secondary tympanic membrane is **_drawn inward_**
61
Walls of cochlear duct are \_\_\_\_: displacement of perilymph by movement of ____ causes \_\_\_\_\_of _____ membrane.
Walls of cochlear duct are **_flexible_**: displacement of perilymph by movement of **_stapes_** causes **_deflection_** of **_basilar_** membrane.
62
Sounds of different frequencies cause waves in basilar membrane with \_\_\_\_\_amplitude (maximal membrane displacement) at different points along membrane: _____ \_\_\_\_\_\_
Sounds of different frequencies cause waves in basilar membrane with **_maximal_** amplitude (maximal membrane displacement) at different points along membrane: **_tonotopic representation_**
63
* High frequency sounds cause waves of \_\_\_\_\_amplitude close to _____ of cochlea
* Low frequency sounds cause waves of _____ amplitude close to _____ of cochlea
* High frequency sounds cause waves of **_maximal_** amplitude close to **_base_** of cochlea
* Low frequency sounds cause waves of **_maximal_** amplitude close to **_apex_** of cochlea
64
upward movement of basilar membrane stereocilia deflected outward (toward stria vascularis) tension causes _____ of mechanically gated ion channels (selective to \_\_) ____ enters cell _____ of hair cell
upward movement of basilar membrane **_stereocilia_** deflected **_outward_** (toward stria vascularis) tension causes **_opening_** of mechanically gated ion channels (selective to **_K+)_** **_K+_** enters cell **_depolarization_** of hair cell
65
depolarization opens voltage-sensitive \_\_\_channels\_\_\_\_enters cell further depolarization and increased ______ \_\_
depolarization opens voltage-sensitive **_Ca+_** channels **_Ca+_** enters cell further depolarization and increased **_intracellular Ca+_**
66
increased intracellular Ca+ binding of \_\_\_\_\_\_-containing vesicles to cell membrane release of ____ into ____ \_\_\_between hair cell and cochlear nerve (afferent) fiber depolarization of afferent fiber action potential transmitted aalong ____ \_\_\_\_\_ \_\_\_\_\_.
increased intracellular Ca+ binding of **_glutamate_**-containing vesicles to cell membrane release of **_glutamate_** into **_synaptic cleft_** between hair cell and cochlear nerve (afferent) fiber depolarization of afferent fiber action potential transmitted along **_cochlear nerve fibers._**
67
Type I sensory neurons make up \_\_\_\_% of neurons in the spiral ganglion
peripheral processes synapse with only one ____ \_\_\_\_ ____ (each ____ hair cell is contacted by peripheral processes of approximately 10 type _____ sensory neurons)
most auditory information conveyed to CNS originates from ____ hair cells
Type **_I_** sensory neurons make up **_90-95%_** of neurons in the spiral ganglion
peripheral processes synapse with only **_1 inner hair cell_** (each **_inner_** hair cell is contacted by peripheral processes of approximately 10 type **_I_** sensory neurons)
most auditory information conveyed to CNS originates from **_inner_** hair cells
68
Type II sensory neurons
* peripheral processes innervate only ___ \_\_\_\_ ___ each peripheral process divides, sending collateral branches to approximately 10 ____ hair cells
* (each ____ hair cell is contacted by peripheral processes of approximately ___ type \_\_\_\_sensory neurons)
Type **_II_** sensory neurons
* peripheral processes innervate only **_outer hair cells_** each peripheral process divides, sending collateral branches to approximately 10 **_outer_** hair cells
* (each **_outer_** hair cell is contacted by peripheral processes of approximately **_4_** type **_II_** sensory neurons)
69
Cochlear nerve also contains efferent fibers from the ____ \_\_\_\_ _____ (in lower pons)
Cochlear nerve also contains efferent fibers from the **_superior olivary nucleus_** (in lower pons)
70
•Outer hair cells are directly innervated by ____ fibers
•Outer hair cells are directly innervated by **_efferent_** fibers
71
\_\_\_\_ hair cells do not receive direct innervation from efferent fibers (type I afferent fibers receive _____ contacts from ____ fibers just before afferent fibers contact inner hair cells)
**_Inner_** hair cells do not receive direct innervation from efferent fibers (type I afferent fibers receive **_axoaxonic_** contacts from **_efferent_** fibers just before afferent fibers contact inner hair cells)
