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neurobio > exam 2 > Flashcards

exam 2 Flashcards

1
Q

-PNS contain highly specialized nerve cells called ____ or (sensory receptors) : convert energy associated with sensory stimuli into electrical signals (receptor potentials or afferent sensory signals)

A

receptors

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2
Q

the process of converting the inert of a sensory stimulus into electrical signal

A

sensory transduction

-stimulus alters the permeability of cation channels in the afferent nerve endings, generating a depolarizing current known as RECEPTOR POTENTIAL or GENERATOR POTENTIAL

-if sufficient in magnitude, the receptor potential allows the afferent neuron to reach threshold –> action potentials occur in the afferent fiber

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3
Q

sensory receptor potentials are ___: their AMPLITUDE REFLECTS INTENSITY OF STIMULUS
***

A

graded

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4
Q

if stimulus is strong enough in sensory receptor potentials, the intensity of stimulus is converted to ___ of action potentials

A

frequency

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5
Q

sensory info from the _______ ______ in the skin

-mediates sensations of the touch, vibration, and pressure

*terminate in skin

A

tactile subsystem

cutaneous mechanoreceptors

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6
Q

sensory info from specialized mechanoreceptors (_____) in muscles, tendons, and joints

-mediates info about the position of body parts
*also mechanoreceptors but are located in muscles, tendons, and joints
*terminate in muscle or tendon

A

proprioceptive system

proprioceptors

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7
Q

sensory info from the ____

-mediates sensations of pain, temp, and coarse touch

*terminate in skin but free nerve ending

A

nociceptive subsystem

nociceptors

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8
Q

somatic sensation is conveyed by ____ ____ ____ from afferent sensory neurons (DRG or CNG neurons)

A

afferent nerve fibers

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9
Q

cell bodies in the afferent sensory system are in the ___ ___ ___ (for body) and in the ___ ___ ___ (for head) of PNS

A

dorsal root ganglia ; cranial nerve ganglia

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10
Q

afferent sensory neurons are ___: peripheral and central components of afferent fibers are continuous, attached to the cell body in the ganglia by a SINGLE PROCESS

A

pseudounipolar

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11
Q

largest diameter, myelinated, supply sensory receptors in the muscles for proprioception

A

A

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12
Q

slightly smaller diameter, myelinated, mostly covert touch sensation

A

A beta

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13
Q

even smaller diameter, lightly or non-myelinated, mostly convert pain and temp sensation

A

A delta and C

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14
Q

rank diameter for somatic sensory afferent

A

A > Abeta> A delta > C

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15
Q

rank conduction velocity for somatic sensory afferent

A

A > Abeta> A delta > C

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16
Q

the area of the skin surface over which stimulation results in a significant change in the rate of action potentials

A

receptive field

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17
Q

what are receptive fields determined by

A

2 point discrimination

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18
Q

the min inter stimulus distance required to perceive 2 simultaneously applied stimuli as distinct

A

2 point discrimination

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19
Q

-fire in the presence of continued stimulation
-provide information about the SPATIAL ATTRIBUTES OF THE STIMULUS, SUCH AS SIZE AND SHAPE

A

slowly adapting (SA) afferents

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20
Q

-fire rapidly when a stimulus is first present, then fall silent int eh presence of continued stimulation

-converys info about CHNAGES IN ONGOING STIMULATION SUCH AS STIMULUS MOVEMENT

A

rapidly adapting (RA) afferents

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21
Q

low thresholds for action potential generation and fire in response to midl to moderate innocuous mechanical stimuli

A

low threshold mechanoreceptors (LTMRs)

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22
Q

high thresholds for action potential generation and only fire in response to intense noxious mechanical stimuli

A

high threshold mechanoreceptors

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23
Q

somatic subsist afferents constitute pathways with different physiological types, conduction velocities, receptive field size, dynamics, and effective stimulus features

A

parallel pathways

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24
Q

afferent fibers are often encapsulated by specialized receptor cells called ___

-____ help tune the afferent fiber to particular features of somatic stimulation

A

mechanoreceptors

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25
Q

afferent fibers of NOCIRECPTORS lack specialized receptor cells

A

free nerve endings

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26
Q

sense points, edges, and curvature

A

Merkel cells

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27
Q

sense objects moved across skin (skin motion)

A

(messier corpuscles)

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28
Q

sense skin vibration

A

pacinian corpuscles

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29
Q

sense skin stretch

A

Ruffini corpuscles

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30
Q

sense skin indentation in hairy skin

A

touch domes

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31
Q

sense skin stroke

A

circumferential endings

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32
Q

sense direction selective air deflection and gentle caress

A

longitudinal lanceolate endings

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33
Q

sensory transduction in mechanosensory afferents is mediated by ___ & ___ mechanosensitive ion channels

A

Piezo 1 &2

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34
Q

detect MECHANICAL FORCES arising within the body itself to provide continuous info about steps of the limbs and other body part in space

A

proprioceptors

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35
Q

detect muscle length

A

muscle spindles

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36
Q

detect muscle tension (muscle force)

A

Golgi tendon organs

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37
Q

the point for point correspondence of an area of the body to a specific point on the CNS

A

somatotopy

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38
Q

shows a orderly somatotropin representation

A

Ventral posterior complex of the tamales

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39
Q

receives projections carrying somatosensory info from the body and posterior head

A

ventral posterior LATERAL nucleus

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40
Q

receives axons from the trigeminal system converting somatosensory info form the FACE

A

ventral posterior MEDIAL nucleus

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41
Q

relays neurons for proprioception for the lower body

A

Clarke’s nucleus

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42
Q

what is the pathway for converting proprioceptive info from the body

A

dorsal root ganglia –> dorsal column nuclei in medulla –> cross midline –> VPL –> contralateral primary somatosensory cortex

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43
Q

somatic sensory afferents constitute pathways with different physiological types, conduction velocities, receptive field size, dynamics, and effective stimulus features

A

parallel pathways

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44
Q

the primary somatic sensory cortex in humans comprises what 4 distinct regions

A

brodmann’s areas 1,2,3a,3b

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45
Q

____ ____ fail to represent the human body in its actual proportions and how a disproportion of the representation of the human body

A

somatotopic maps

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46
Q

neurons in area 3b and 1 respond to primary ____ stimuli

A

cutaneous

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47
Q

3a respond mail to the simulation of

A

proprioceptors

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48
Q

neurons in area 2 process what 2 stimuli

A

tactile and proprioceptive stimuli

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49
Q

area ___ receives the most input from VP complex and provides a dense projection areas to 1 & 2

**serves as ab obligatory first step in cortical processing of somatosensory info

A

area 3b

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50
Q

profound deficiencies in ALL textile sensation

A

area 3b deficit

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51
Q

partial deficits where the us an inability to discriminate the texture of objects

A

area 1 deficit

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52
Q

partial deficits – inability to discriminate the size and shape of objects

A

area 2 deficit

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53
Q

primary somatosensory cortex neurons with similar response properties are clustered together into ___ ___ ____

A

functionally distinct column

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54
Q

3rd degree neurons in ____ VPL or VPM face in thalamus

– somatotopy

A

contralateral

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55
Q

3rd degree neurons in ____ primary somatosensory cortex

A

contralateral

**3b –> 1 or 2

-somatotopy
-functional column
-plasticity

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56
Q

nociceptors arise form neurons in ____ root ganglia for face

A

dorsal

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57
Q

what axons are associated with nociceptors for pain sensation

A

A delta myelinated and C fibers unmyleinated

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58
Q

convey a sharp pain first

A

a delta fibers

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59
Q

conniver delayed, diffuse, and longer lasting second pain

A

C fibers

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60
Q

noxious heat (above 43 degrees celsius) is conferred by what family

A

transient receptor potential (TRP) channels, TRPV1, found in both c and a delta fibers

-in open TRP channels allow can influx of sodium and calcium the initiates the generation of action potentials in the nociceptive fibers

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61
Q

in the anterolateral system (column) , axons of 2nd order neurons form the ____ ____

A

anterolateral column

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62
Q

dorsal column deal with what 3 things

A

deep touch, proprioception, vibration

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63
Q

anterolateral column deals with what 2 things

A

pain and temp

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64
Q

in dorsal column, the column arises from what

A

mostly axons from the FIRST order DRG neurons

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65
Q

in anterolateral column, the column arises from what

A

mostly axons from the SECOND order dorsal horn neurons

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66
Q

location of crossing midline in dorsal column

A

brainstem or cervical spinal cord

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67
Q

location of crossing midline in anterolateral column

A

spinal cord

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68
Q

column ascending location in spinal cord in dorsal column

A

ipsilateral side of spinal cord

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69
Q

column ascending location in spinal cord anterolateral column

A

contralateral side of spinal cord

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70
Q

stimuli in the inputs and surrounding area s that would ordinarily be perceived as slight painfully are perceived as significantly more so resulting from both peripheral and central sensitization

A

hyperalgesia

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71
Q

induction of pain by a normally innocuous stimuli

A

allodynia

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72
Q

chronic, intensely painful experience because the afferent fibers or central pathways themselves are damaged

A

neuropathic pain

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73
Q

peripheral sensitization results in potential of ___ channel

A

trp

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74
Q

what is involved in placebo affect

A

ENDOGENOUS OPIOIDs

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75
Q

activation of mechanoreceptors modulates the transmission of nociceptive info to higher center

A

gate control theory of pain

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76
Q

most sensory receptor cells derives from the epithelium and form columnar epithelium like structure for the reception of external stimuli

A

sensory epithelium (neuroepithelium)

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77
Q

all sensory receptors cells are ___ and compartmentalized

A

polarized

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78
Q

contains neurons sensitive to light and capable of converting light to electrical signals (phototransduction) and transmitting the signals to central targets

A

retina

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79
Q

circular area where the blood vessels enter the eye and also the site where retinal axons leave the eye and travel through the optic nerve

*contains no photoreceptors and is the blind spot

A

optic disk

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80
Q

an oval spot near rite center of the retina and is the region of the retina that supports high visual acuity

A

macula lutea

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81
Q

acuity is the greatest at the center of the macula, a small pit in the retina

A

fovea

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82
Q

cell layer just outside the neruosensory retina that reduces the backscattering go the light and plugs critical role in maintaining the phototranscurion machinery of retinal photoreceptors

A

retinal pigment epithelium

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83
Q

retina contains what 5 basic classes of neurons

A
  1. photoreceptors (rods and cones)
  2. bipolar cells
  3. ganglion cells
  4. horizontal cells
  5. amacrine cells
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84
Q

cell bodies of photoreceptors (rods and cones)

A

outer nuclear layer

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85
Q

the processes and synaptic contacts btw photoreceptor terminals and bipolar cells (and horizontal cells)

A

outer plexiform layer

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86
Q

cell bodies of bipolar cells, horizontal cells, and amacrine cells

A

inner nuclear layer

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87
Q

the process and synaptic contacts btw bipolar cells and amacrine cells and dendritic processes of ganglion cells

A

inner plexiform layer

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88
Q

cell bodies of ganglion cells

A

ganglion layer

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89
Q

the most direct pathway of info flow from photoreceptors to the optic nerve

A

3 neuron chain –> photoreceptor –> to bipolar cell –> ganglion cell

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90
Q

what cells mediate lateral interactions in the outer na dinner plexiform layers

A

horizontal and amacrine

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91
Q
  1. maintain phototransduction machinery of retinal photoreceptors
  2. reduced backscattering
A

pigment epithelium

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92
Q

what is the visual info flow by 3 neuron chain

A

photoreceptor –> to bipolar cell –> ganglion cell

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93
Q

composed of membranous disks containing light sensitive photopigments

A

outer segment

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94
Q

contains the cell nucleus and give rise to synaptic terminals that contact bipolar or horizontal cells

A

inner segment

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95
Q

shining light on either a rod or cone leads to a mem ___ rather than ____

-saturates around -65 mV

A

hyperpolarization ; depolarization

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96
Q

light activation causes a ___ change in mem potential

A

graded

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97
Q

______ and light induced changes in the electrical active of photoreceptors

A

cGMP

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98
Q

absorption of light by the photoreceptor (increases or reduces? ) the cGMP conc

A

reduces

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99
Q

prices that photoreceptors convert light energy to electrical signals

A

phototransduction

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100
Q

-GPCRs

proteins with photopigment containing light absorbing chromophore retinal

A

opsins

101
Q

-a GCPR

-opsin in rods, contains 7 transmit domains forming a pocket to enclose retinal molecule

A

rhodopsin

102
Q

phototransduction process

A
  1. photoreceptors absorb photon of light
  2. double bonds breaks and retinal changes form 11 cis to all trans isomers
  3. conformation change of rhodopsin leads to activation of transducin
  4. transducin activates phosphodiesterase that hydrolyze cGMP
  5. lowering of cGMP conc in the outer segment leads to channel closure and hyperolarization of the cell
103
Q

mag of the phototransduction amplification varies with the prevailing level of illumination

-photorecpetors are most sensitive to light at low illumination levels

*when illumination levels increase, sensitivity decreases, preventing the receptors from saturating to end the operating range of light intensities

-ca2+ conc in the outer segment play a key role in light adaptation

A

light adaptation

104
Q

very low postal resolution acuity but very sensitive to light

A

rod system

105
Q

very high spatial resolution (specialized for acuity) but relatively insensitive to light; allows use to see color

A

cone system

106
Q

only rod mediated perception at the lowest levels of illumination

A

scotopic vision

107
Q

both rods and cones contribute to perception

A

mesopic vision

108
Q

illumination increases to level of all mem channels are closed in rods and rod response to light saturates

**only cone mediated color perception

A

photopic vision

109
Q

-slow adaption
-high convergence
-high sensitivity
-reduced resolution

A

rod

110
Q

-fast adaption
-low convergence
-low sensitivity
-increased acuity

A

cone

111
Q

___ don’t saturate at high levels of illumination

A

cones

112
Q

___ have high degree of convergence

A

rods

113
Q

in fovea ___ density increases 200 fold and in the center of the fovea (foveola) – rod free and avascular (no blood vessel)

A

cones

114
Q

superiority of acuity of the cone system is due to

A
  1. 1-1 relationship btw cone and ganglion cell
  2. greater cone density in the fovea
  3. displacement of the inner layer s of the retina minimize photon scattering
  4. no retinal blood vessels in central region of fovea
115
Q

rods contain what single photopigment protein

A

rhodopsin

116
Q

cones have what 3 photopigment proteins

A

3 different wavelengths

short, medium, and long wavelength cones most sensitive to blue green and red lights

117
Q

normal color vision

A

trichromatic

118
Q

impairment in perception of long wavelengths

-difficulty in discrimination of red and green

A

protanopia

119
Q

impairment in the perception of medium wavelengths

-difficulty in discrimination of red and green

A

deuteranopia

120
Q

produces a burst of action potentials when a spot of light in the receptive field center and reduces the rate of discharge when a dark spot in the receptive center (increase discharge rate in luminance increment)

-ionotropic glutamate receptor

A

on center ganglion cell

121
Q

produces a burst of action potentials when a spot of dark in the receptive field center and reduces the rate of discharge when a light spot in the receptive center (increase discharge rate in luminance decrement)

-ionotropic glutamate receptor

A

off center ganglion cell

122
Q

use metabotropic glutamate receptor

glutamate is inhibitory and causes hyperpolarization

A

on center bipolar cells

123
Q

use ionotropic glutamate receptor and glutamate is excitatory and cause depolarization

A

off center bipolar cells

124
Q

when the concentric surrounding region off the receptive field is stimulated, it antagonizes the response to stimulation of the receptive field center

A

center surround antagonism

125
Q

___ cell mediated depolarization antagonize phototransduction induced hyperpolarizatino of the center photoreceptor

A

horizontal

126
Q

Photoreceptor synapses with off‐center bipolar cells are____‐ ____: the direction of membrane potential (Vm) change of the bipolar cell (de‐ or hyper‐polarization) is the same as that in the photoreceptor

**mem potential change in bipolar cell same as photoreceptor

A

sign-conserving

127
Q

Photoreceptor synapses with on‐center bipolar cells are ___‐ _____: the change in the Vm of the bipolar cell is the opposite of that in the photoreceptor

**mem potential change in bipolar cell opp of photoreceptor

A

sign inverting

128
Q

response during light stimulation in the center: light increment hyperpolarizes photoreceptor and decreases glutamate release → glutamate is inhibitory, so on‐center bipolar cells are free from the hyperpolarization and they depolarize → On‐center ganglion cells increase discharge rate

A

on center ganglion cell

129
Q

response during light stimulation in the center: light increment hyperpolarizes photoreceptor and decreases glutamate release → glutamate is excitatory, so off‐center bipolar cells withdraw from depolarization and they hyperpolarize → Off‐center ganglion cells decrease discharge rate

A

off center ganglion cell

130
Q

Circuitry responsible for generating ____ ____ center responses of retinal ganglion cells

A

receptive field

131
Q
  1. light stimulation hyper polarizes the surround cone
  2. surround horizontal cell becomes hyper polarized and decreased GABA release to center cone
  3. center cone frees from inhibition and depolarizes to offset light induced hyperpolarization in the center receptive field
  4. center cone increases glutamate release to inhibit and hyper polarize on center bipolar cell
  5. on center ganglion cell also hyperpolarize and firing rate decrease
A

Lateral interaction from horizontal cells in the retina

132
Q

rod convergence

A

high 15:30 - 1 to ganglion cell

133
Q

rod is activated in

A

scotopic and mesopic vision

134
Q

cone is activated in

A

photopic and mesopic vision

135
Q

Center‐surround antagonism allows ganglion cells to detect _____ _____ in the border

A

luminance contrast ***

136
Q

Ganglion cells are relative insensitive to different levels of _____ ____

A

diffuse illumination

137
Q

Ganglion cells are sensitive to differences between the level of illumination that falls on the receptive field center and the level of illumination that falls on the surround the ____ ____

A

luminance contrast

138
Q

center surround antagonism also contributes to ___ ___

A

light adaptation

139
Q

Two functions of center‐surround antagonism

A
  1. Detect luminance contrast in the border (make ganglion
    cells sensitive to light‐dark borders in the visual scene)
  2. Light adaptation to increase dynamic range of encoding in ganglion cells
140
Q

what 2 mechanism in the retina help achieve light adaptation

A
  1. Photoreceptor light adaptation mediated by decreasing intracellular calcium concentration
  2. Retinal circuitry light adaptation mediated by surround antagonism from horizontal cells to the center cone cel
141
Q

what is the function of external ear

A

boost sound pressure 100 fold

142
Q

middle ear consists of

A

-tympanic mem
-malleus, incus, stapes (middle ear)

143
Q

a membrane‐covered opening at the base of the cochlea between middle and inner ear, the site where the bones of the middle ear contact the inner ear

A

oval window

144
Q

function of middle ear

A

boost the pressure 200 fold

145
Q

small coiled structure of the peripheral auditory system

A

cochlea

146
Q

the other opening of the two openings (oval and round windows) from the middle ear into the inner ear

A

round window

147
Q

flexible structures in the middle of cochlea and bisect cochlea into the cochlear partition

A

basilar and tectorial mem

148
Q

two fluid‐filled chambers on each side of the cochlear partition; connected through each other by an opening

*fluid is perilymph

A

Scala vestibuli and Scala tympani

149
Q

distinct channel rums within the cochlea partition

*fluid is endolymph

A

scala media

150
Q

primary auditory neurons transmit sound information from
hair cells to the CNS

A

spiral ganglion neurons

151
Q

the receptor organ (or sensory epithelium) for hearing in the cochlea, composed of mechanosensory hair cells (inner hair cells and outer hair cells) and supporting cells

A

organ of corti

152
Q

-bears the organ of Corti and hair cells are situated on top of it

-spectral decomposer to decompose a sound stimulus to it’s frequency component

A

basilar mem

153
Q

covers the mechanically‐sensitive hair bundles of the hair cells

A

tectorial mem

154
Q

cause maximum displacement of basilar membrane at the basal
end

A

high frequency sound

155
Q

cause maximum displacement of basilar membrane at
the apical end, giving rise to a topographical mapping of frequency called tonotopy

A

low frequency sound

156
Q

spatial arrangement of where different sound frequencies are processed in
different regions of the auditory system

A

tonotopy

157
Q

vertical component of the traveling wave is translated into a shearing motion between the two membranes to bend the tiny processes, called _____ (or hair bundles), that protrude from the apical ends of the hair cells, leading to opening of ____ ___ ____

A
  1. stereocilia
  2. mechanoelectrical transducer (MET) channels
158
Q

T/F sterocilia are NOT graded in height

A

FALSE. THEY ARE

159
Q

Fine filamentous structures, known as ___ ___ , run in parallel to the plane of bilateral symmetry, connecting tips of adjacent stereocilia

A

tip links

160
Q

the process that hair cells convert mechanical energy from sound waves to electrical signals

A

mechanoelectrical transduction

161
Q
  1. Displacement of the hair bundle parallel to the plane of symmetry in the direction of the tallest stereocilia stretches the tip links, opening the cation‐selective mechanoelectrical transducer (MET) channels located at
    the end of the link and generating a graded receptor potential to depolarize the hair cell (hair cells do not fire action potentials)
  2. Depolarizing graded receptor potentials cause opening of voltage‐gated Ca2+ channels and transmitter (glutamate) release accordingly, eliciting action potentials in afferent nerve terminal of spiral ganglion neurons
A

mechanoelectrical transduction

162
Q

Endolymph in scala media is K+‐rich, Na+‐poor due to ion‐pumping cells in the stria vascularis pumping K+ into endolymph

Endolymph is about 80 mV more positive than perilymph or 125 mV more positive than the inside of hair cell

The steep electrical gradient drives K+ through open transduction channels into the hair cell and depolarize the hair cell, causing the opening of voltage‐ gated Ca2+ and K+ channels located in the membrane of the cell soma

Because the perilymph at basal end of hair cell is K+‐poor, Na+‐rich and because EKbasal (‐85 mV) is more negative than hair cell’s resting potential, K+ efflux through somatic K+ channels to repolarize the hair cell

A

ionic basis of mechanotransduction in hair cell

163
Q

____ influx and efflux through two different K+ channels serves both to depolarize and repolarize the hair cell

A

K+

164
Q

a plot of auditory threshold intensity at various frequencies for a single auditory nerve fiber

A

tuning curve

165
Q

(frequency at which a given spiral ganglion neuron responds to the smallest sound intensity

A

characteristic frequency

166
Q

cochlear amplifier to amplify the sound

A

outer hair cells

167
Q

self‐generated sounds from outer hair cells due to their electromobility

A

Otoacoustic Emissions (DPOAE)

168
Q

can measures outer hair cell function in the inner ear

A

otoacoustic emission test (OAE)

169
Q

The ____ ______ (or frequency map) of the cochlea is retained at all levels of the central auditory system

A

tonotopic organization

170
Q

electromobility helps to ____ sound

A

amplify

171
Q

peripheral component of the vestibular system formed by the interconnected chambers/canals continuous with the cochlea

A

Vestibular labyrinth

172
Q

Vestibular labyrinth also uses (mechanosensory) ____ ____ as
the sensory receptor cells to transduce physical motion into neural impulses

A

hair cells

173
Q

The vestibular labyrinth is consists of two ____ (Greek for “ear stones”) organs, the ____ and ____, and three _____ canals

A

otolith; utricle; saccule; semicircular

174
Q

___ and ____ are specialized to respond to linear accelerations of the head and static head position relative to the gravitational axis

A

utricle and saccule

175
Q

______ _____ are specialized to respond to rotational accelerations of the head

A

semicircular canals

176
Q

Vestibular hair cells are located in the utricle and saccule and the ______ of three
semicircular canals

A

ampullae

177
Q

Movement of the
stereocilia toward the kinocilium opens
mechanically gated
channels, _______ vestibular hair cells and
causing transmitter release
onto (and excitation of) the
vestibular nerve fibers of
vestibular ganglion neurons

A

depolarizing

178
Q

Movement of the stereocilia in the direction away from the kinocilium closes the channels, ______ vestibular hair cells and reducing vestibular nerve firing

A

hyperpolarizing

179
Q

firing rates of vestibular fibers can _____ or _____ to faithfully mimic the receptor potentials produced by vestibular hair cells (different to auditory hair cells, which mostly use depolarization to encode signals)

A

increase/decrease

180
Q

In the utricle and saccule, a specialized area called the _____ divides the hair cells into two populations with opposing hair bundle polarities

A

striola

181
Q

sensory epithelium of the utricle and saccule, which consists of hair cells and associated supporting cells

A

macula

182
Q

the otolithic membrane, in which are embedded crystals of calcium carbonate called ____ (ear stone)

A

otoconia

183
Q

A tilt of the head to one side has ____ effects on corresponding hair cells of the two utricular maculae or saccular maculae

A

opp

184
Q

linear movements in the vertical plane

A

saccule

185
Q

linear movements in the horizontal plane

A

utricle

186
Q

The kinocilia are directed ____ the striola in the utricular macula but point ____ from the striola in the saccular macula

A

toward; away

187
Q

response to head tilt

A

tonic (sustained) hair displacement

188
Q

response to linear acceleration

A

transient hair bundle displacement

189
Q

sensory epithelium of semicircular canals inside the ampulla, containing the hair cells

A

crista

190
Q

a dome‐shaped gelatinous mass over hair bundles, where hair bundles extend into

A

capula

191
Q

The semicircular canals sense head ____

A

rotations

192
Q

When rotating or turning the head to right, vestibular hair cells in the right horizontal canal are
_____ and vestibular hair cells in the left horizontal canal are _____

A

depolarized; hyperpolarized

*whatever side u turn, that side depolarizes

193
Q

The maximum firing rates corresponds to the period of ____

A

acceleration

194
Q

maximum inhibition corresponds to the period of _____

A

deceleration

195
Q

During the constant‐velocity phase, firing rates return to a _____ level

A

baseline

196
Q

vestibulo‐ocular reflex (VOR) for ______ _____

A

stabilizing gaze

197
Q

Central vestibular processing is ______ _____ and vestibular inputs are integrated with inputs from visual and somatic sensory system

A

multisensory nature

198
Q

Many neurons in vestibular nuclei function as _____ _____ (a.k.a upper motor neurons)

A

premotor neurons

199
Q

Processesinformationabouttheidentity,
concentration, and quality of a wide range of airborne, volatile chemical stimuli

A

odorant

200
Q

Axons (olfactory nerve, cranial nerve I) arising from receptor cells project directly to neurons in the _____ _____(in the CNS)

A

olfactory bulb

201
Q

sensory epithelium of olfaction

A

olfactory epithelium

202
Q

sensory receptor cells of olfaction

A

olfactory receptor neurons

203
Q

Neurons in the olfactory bulb send projections to the _____ cortex in the temporal lobe and to other forebrain structures via an axon pathway known as the ______ _____

A

pyriform; olfactory tract

204
Q

t/f Olfactory system does include a thalamic relay from primary receptors to a cortical region (different than other sensory systems, which all have the thalamic relay)

A

f it does NOT

205
Q

a three‐layered archicortex dedicated for processing olfactory sensory information and is phylogenetically older than the six‐layered neocortex

A

pyriform cortex

206
Q

relays information directly to hypothalamus and amygdala for feeding, reproduction, and aggressive behaviors

A

olfactory bulb

207
Q

bipolar sensory receptor cells give rise to unmyelinated axons at their basal surface to transmit information centrally

-polarized and compartmentalized

*EXPRESSES ONLY ! OF THE ODORANT RECEPTOR GENES

A

Olfactory receptor neurons (ORNs)

208
Q

several microvilli protrude from a single knoblike dendritic process (olfactory knob) at the apical surface of an ORN
– olfactory cilia extend into a thick layer of mucus

A

Olfactory cilia

209
Q

secret mucus

A

Bowman’s glands

210
Q

a population of neural stem cells that divide to give rise to new receptor neurons

A

Basal cells

211
Q

structural support and detoxify potentially dangerous chemicals

A

sustentacular (supporting) cells

212
Q

mucus layer and epithelium with neural and supporting cells

A

nasal mucosa

213
Q

In rodents, most ORNs are renewed every 6 to 8 weeks by new ORNs from what cells

A

basal cells

214
Q

glial cells derived from olfactory epithelium to surround axons in the olfactory nerve and bulb and to support the growth of new axons through a mature nervous system

A

Olfactory ensheathing cells

215
Q

Odor transduction in the olfactory epithelium begins with odorant binding to specific _____ _____ _____ concentrated on the external surface of olfactory cilia

-encoded by the odorant receptor gene family
-GPCRs

A

odorant receptor proteins

216
Q
  • ORNs express an olfactory‐specific heterotrimeric G‐protein, Golf
  • Alpha subunit of Golf dissociates upon odorant binding to receptors and then activates adenyl cyclase
    III (ACIII), an olfactory‐specific adenylate cyclase
  • An increase in cyclic AMP (cAMP) opens cyclic nucleotide‐gated channels that permit entry of Na+
    and Ca2+ (mostly Ca2+), depolarizing the neurons
  • Depolarization is further amplified by Ca2+‐activated Cl‐ current and is conducted passively from cilia to the axon hillock of the ORN, where action potential are generated via voltage‐gated Na+ channels and transmitted to the olfactory bulb
  • In response to elevated Ca2+, and Na+/Ca2+ exchanger extrudes Ca2+ and transports Na+ to re‐ polarize the membrane
  • Increases in Ca2+ and activation of calcium/calmodulin‐dependent kinase II (CaMKII) restore the Golf and diminish cAMP levels via activation of phosphodiesterases
A

odor transduction

217
Q

Most randomly selected single ORNs have _____ _____ ____ to a variety of odorants

A

broadly tuned responses

218
Q

spherical accumulations of neuropil lie just beneath the surface of the bulb and are the synaptic target of the primary olfactory axons

A

glomeruli

219
Q

Within each glomerulus, ORN axons contact apical dendrites of _____ cells, the _____ _____ neurons of the olfactory bulb,

A

principal projection

220
Q

Axons from ORNs that express a particular odorant receptor gene ____ on a small subset of bilaterally symmetrical glomeruli

A

converge

221
Q

_________ increases the sensitivity of mitral cells to ensure maximal fidelity of odor detection and also average out uncorrelated “background” noise

A

convergence

222
Q

Olfactory bulbs employs a _____ ______ _____ that cues in on a small number of dominant chemicals within a mixture

A

sparse coding mechanism

223
Q

_____ cell axons provide the only relay for olfactory information to the rest of the brain

A

mitral

224
Q

The mitral cell axons from each olfactory bulb form the ____ ____ ____ that project ipsilaterally to the pyriform cortex and other forebrain regions

A

lateral olfactory tract

225
Q

Individual pyriform cortical cells are _____ ____ to different odors than is the case in the olfactory bulb

A

broadly tuned

226
Q

the chemical constituents of food interact with receptor proteins on _____ _____ (sensory receptor), which are located in epithelial specializations called _____ _____ (sensory epithelium of the taste system)

A

taste cells; taste buds

227
Q

Taste cells are innervated by sensory afferent axons from neurons in the _____ _____ _____

A

cranial nerve ganglia

228
Q

The central axons of these sensory afferent neurons in the cranial nerve ganglia project to the nucleus of the solitary tract (a.k.a. _______ nucleus

A

gustatory nucleus

229
Q

Axons from the gustatory nucleus project to ventral posterior medial nucleus of thalamus, which in turn projects to _____ and _____ taste cortex

A

insular and frontal

230
Q

pathway of taste system

A

taste cells in taste buds –> relay neurons in cranial nerve ganglia –> gestatory nucleus in brainstem –> VPM in thalamus –> insular and frontal cortex

231
Q

multicellular protuberances surrounded by local invaginations (trench) in the tongue
epithelium

A

taste orillas

232
Q

(sensory epithelium) are distributed along the lateral surfaces of the papillar
protuberances and in the trench walls

-have lifetime of ~2 weeks and are regenerated by BASAL CELLS

A

taste buds

233
Q

found only on the anterior of the tongue and contain 25% of total taste bud

A

fungiform papillae

234
Q

form a chevron at the rear of the tongue and contain 50% of total taste buds

A

9 circumvallate papillae

235
Q

on the posterolateral tongue and contain remaining 25% of the total taste buds

A

foliate papillae

236
Q

the taste system detects five perceptually distinct categories of tastants

A

salt, sour, sweet, bitter, and umami

237
Q

The tip of the tongue is most responsive to

A

sweet, umami, and salty compounds

238
Q

Sour and bitter taste sensitivity is lowest toward the tip and greatest on

A

the sides and back of the tongue

239
Q

Type II cell:

A

sweet, bitter, umami, or salty

240
Q

Type III cell

A

sour

241
Q

______ _____ is initiated in the apical domain of the taste cells to open ion channels to generate electrical signals by graded receptor potentials (and later the action potentials) for neurotransmitter release at the basal domain
Type I cell: glial‐like supporting cell
Type II cell: sweet, bitter, umami, or salty

A

chemosensory transduction

242
Q

Neurotransmitters for taste cells

A

serotonin, ATP

243
Q

Ion channels for ____ and _____ tastes

A

salty and sour

244
Q

G‐protein‐coupled receptors (GPCRs) for ____, _____, _____ tastes

A

sweet, bitter, and umami

245
Q

Salty and sour tastes are elicited directly by ____ ____ such as positively charged ions in
salts (Na+) or the H+ in acids

A

ionic stimuli

246
Q

The salty taste is initiated by the amiloride‐sensitive Na+ channels (called _______)

A

ENaCs

247
Q

Sour stimuli permeate into cells through ______ channels or via passive diffusion, and cytoplasmic protons block an inward‐rectifier K+ channel, resulting in depolarization

A

OTOP1

248
Q

Sweet and umami receptors are heterodimeric GPCRs that share the common TAS1R3 subunits, paired with the TAS1R2 for _____, or with the TAS1R1 for _____

A

sweet; umami

249
Q
A

neurobio (7 decks)

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