Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

neurobio > exam 3 > Flashcards

exam 3 Flashcards

1
Q

Lower motor neurons and local circuit neurons (interneurons) in the spinal cord and brainstem

**Functions to commend for movement (reflexive or voluntary)

A

subsystem 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

a.k.a ventral horn neurons) innervate the skeletal muscles of the head and body

A

lower motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

(a.k.a interneurons) receive sensory inputs and descending projections from upper motor neurons

A

local circuit neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sensory neuron to lower motor neuron without involvement of upper motor neuron in the cortex

A

reflexive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

sensory neuron to upper motor neuron in the cortex and then to lower motor neuron

A

voluntary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

____ ___ neurons located in the** ventral horn of the spinal cord gray matter

A

lower motor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Upper motor neurons (UMNs) in brainstem or cerebral cortex

A

Subsystem II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

____ ____ neurons send descending axons to synapse with the local circuit neurons or rarely with the lower motor neurons

A

upper motor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

___ upper motor neurons are for the initiation of voluntary movements and for skilled movements

A

cortical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

_____ upper motor neurons are for regulating muscle tone and integrating sensory inputs for postural control

A

brainstem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Basal ganglia (a group of forebrain structures)
Prepare upper motor neuron circuits for the initiation of the voluntary
movement and suppress unwanted movement

A

Subsystem III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

cerebellum
-Detects and attenuates the difference or“motor error” between an intended movement and the actual movement (correct motor error

A

subsystem 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

all the motor neurons innervating a single muscle are grouped together into a rod‐shaped cluster called the ____ ____ _____ for that muscle

A

motor neuron pool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

____ low motor neuron pools innervate the axial (proximal) musculature

A

medial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

more _____ pools innervate muscles located progressively more laterally in the body

A

lateral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

___ low motor neuronal pools govern postural control and receive input from brainstem upper motor neurons

A

medial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

_____ motor neuron pools that innervate the distal extremities are for the execution of skilled behavior and are governed by projections from motor cortex upper motor neurons

A

lateral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

___ Lower motor neurons innervates the extrafusal muscle fibers that actually generate the forces need for posture and movement

A

alpha

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

____ lower motor neurons innervate intrafusal muscle fibers in muscle spindles and they adjust the gain of muscle stretch reflex

A

gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

the axon from a single α motor neuron branches within muscles to synapse on many extrafusal fibers

**ON EXAM
*ONLY CONTAINS ONE MOTOR NEURON AS OPPOSED TO MANY: MOTOR NEURON POOL

A

motor unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

-generate small forces
-most resistant to fatigue
-Low threshold for activation and are tonically active for motor acts requiring sustained effort

A

slow motor units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

-generate large force
-easily fatigue

A

fast fatigable (FF) motor units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

-medium force
-resistant to fatigue

A

fast fatigue resistant motor units (FR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

gradual increases in muscle tension (or force) results from the progressive recruitment of motor units in a fixed order (S → FR → FF), according to their size

-Low threshold S motor units are recruited first, then FR motor units, and finally, at the highest levels of activity, the FF motor units

A

size principle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The number of active motor units and their rate of ____ both increase with voluntary force

A

firing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q
  1. The orderly recruitment of different types of motor units (size principle, S→FR→FF)
  2. An increase in lower motor neuron firing frequency
A

Graded increases in muscle force (tension) are mediated by

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

for muscle stretch reflex, what is the Sensory signal:

A

muscle spindles, the sensory receptors in most muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Stretch reflex circuitry is a negative feedback loop used to maintain _____ ____ at a desired value

A

muscle length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

____ motor neurons adjust the gain of the muscle stretch reflex

A

gamma γ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is the sensory signal for authentic inhibition reflex

A

Golgi tendon organs, the sensory receptors in the tendon
* Afferent fibers of Golgi tendon organs terminate on collagen fibers of the tendo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

____ ____ organs are mostly sensitive to increases in muscle tension & are relatively insensitive to passive stretch

A

Golgi tendon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

when muscles contract is firing rate changing with Golgi tendon or muscle spindle

A

Golgi tendon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Autogenic inhibition reflex regulate ____ _____ to a desired level

A

muscle tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

____ ____ are sensitive to both stretch and contraction of muscle (monitor and maintain muscle length)

A

muscle spindle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

____ ____ ___ are sensitive to muscle contraction but relatively insensitive to muscle stretch (monitor and maintain muscle tension)

A

Golgi tendon organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

control the timing and coordination of rhythmic movements

A

central pattern generators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

are biological neural networks that produce rhythmic patterned outputs without sensory feedback and without descending upper motor neuron inputs

A

central pattern generators (CPGs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

flexor muscle contracts; the limb is flexed to leave the ground and then brought forward to begin the next stance phase

A

swing phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

extensor muscle contracts; the limb is extended and placed in contact with the ground to propel the animal forward

A

stance phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

t/f Each limb appears to have its a group of central pattern generators for the alternating flexion and extension of the limb during locomotion

A

FALSE; each limb has its OWN CENTRAL PATTERN GENERATORS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Homonymous muscle* contraction, heteronymous muscle* relax

A

muscle stretch reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Homonymous muscle* relax, heteronymous* muscle contraction

A

autogenic inhibition reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Local circuit neurons and LMNs generate rhythmic firing, flexor and extensor muscles contract alternatively

A

central pattern generators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

muscle directly innervated by the sensory afferents

A

*Homonymous muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

antagonistic muscle not innervated by the sensory afferents

A

*Heteronymous muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

where is the upper motor neurons located

A

cortex and brainstem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

location of upper motor cortex in cortex

A
  1. primary motor cortex
  2. premotor cortex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

location of upper motor cortex in brainstem

A

vestibular nuclei
2. reticular formatiojn
3. superior colliculus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Axons of UMNs in brainstem course through the anterior‐medial white matter of the spinal cord and terminate on ____ ____ ____ (interneurons and lower motor neurons) in *both sides of the spinal cord

A

medical cell groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Axons of UMNs in motor cortex course through the lateral white matter of the spinal cord and terminate in ____ _____ _____(interneurons and lower motor neurons) in the contralateral side of the spinal cord

A

lateral cell groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

mediate the expression of skilled voluntary movements of distal extremities (terminate on the contralateral side of the spinal cord)

A

UMN in motor cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

govern posture and balance mechanisms of axial muscles (terminate on both sides of the spinal cord)

A

UMNs in brainstem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

the axons of the upper motor neurons in the motor cortex descend and terminate in the contralateral spinal cord

A

Corticospinal tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

the axons of the upper motor neurons in the motor cortex descend and terminate in the brainstem bilaterally (bulbar refers to brainstem nuclei)

A

Corticobulbar tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

The discharges of a given UMN facilitates contractions of single or several different muscles?

A

several different muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

the discharges of a given UMN peripheral muscle group is referred to as the ______ ______ of the UMN

A

muscle field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

The UMNs in the primary motor cortex controls ______, rather than the contraction of individual muscles

A

movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

_____ movements are mapped in the primary motor cortex

A

purposeful

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

neurons in the primary motor cortex encode intentions for movements in ____ _____ ____ (within arm’s length)

A

central personal space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

the commands to perform precise movement patterns are encoded by the concurrent discharges of a large population of UMNs

A

population coding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

four interconnected frontal lobe areas that lie anterior to the primary motor cortex

A

premotor cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

UMNs in lateral premotor cortex encode intentions (or the selection) for movements that are oriented toward ______ space (beyond arm’s length)

A

extrapersonal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

a subset of UMNs in premotor cortex fire in response to not only preparation of a particular movement, but also to OBSERVATION of the particular movement being performed by others

A

mirror neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q
  1. Encode movements but not muscle contraction
  2. Encode intentions for movements in central personal space
  3. These movements are
    purposeful/pre‐programmed (behaviorally useful) movements
  4. Population coding: each precise movement is encoded by the concurrent discharges of a large population of UMNs relevant to the movement
A

primary motor cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

encode intentions for movements that are oriented toward extrapersonal space

A

premotor cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

control the maintenance of balance and the regulation of posture by REFLEXIVE movement

A

vestibular complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

control the maintenance of balance and the regulation of posture by voluntary movement

A

voluntary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

control the orientating head and eye movement

A

superior colliculus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

what is the Vestibulo‐cervical reflex (VCR) pathway

A

1.semicircular canals
2. UMNS in MEDIAL vestibular nucleus
3. LMNs in CERVICAL spinal cord
4. neck muscles
5. regulates head pos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

what is the Vestibulo‐spinal reflex (VSR) pathway

A
  1. otolith organs
  2. UMNs in lateral vestibular nucleus
  3. LMNs in thoracic and lumbar spinal cord
  4. body muscles
  5. regulates posture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

a network of circuits in the core of the brainstem that extends from the rostral midbrain to the caudal medulla

A

reticular formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

what is the corticotreticular pathway

A
  1. UMNs in cortex
  2. UMNs in reticular formation
    (through reticulospinal tract)
  3. LMN in thoracic/lumbar spinal cord
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Vestibular nuclei and reticular formation both provide information to the spinal cord for posture maintenance but use ____ mechanisms

A

different

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

UMNs in vestibular nuclei ensure a rapid compensatory ______ ____ response to any existing postural instability

A

feedback reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

UMNs in reticular formation initiate
_______ ______ adjustments that stabilize posture during ongoing movements

A

feedforward voluntary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Postural control during movement by _____ ____ entails an anticipatory feedforward mechanism

A

reticular formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Vestibular nuclei generate a ____ ____ response initiated by sensory inputs that detect existing postural instability to adjust posture

A

feedback reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

what is the cortico-collicular pathway

A
  1. senosry inputs from visual jcortex
  2. UMNs in cortex
  3. UMNs in superior colliculus
    (via colliculospinal tract or UMNs in reticular formation)
  4. LMNs in cervical spinal cord
  5. orienting head and eye movement (saccade)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

what does the basal ganglia include

A
  1. Corpus striatum (caudate + putamen)
  2. globus pallidus (internal + external)
  3. substantia nigra (pars compacta + pars reticulata
  4. sub thalamic nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

what is the education of basal ganglia in control of voluntary motor movement

A

initiation of intended voluntary movement and suppression of unwanted movement (action selection)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

does thalamus belong to the basal ganglia ***

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

what is the input zone

A

corpus striatum

80
Q

The basal ganglia receives two major inputs:
1. The glutamatergic input (excitatory) from the ______ _____ (corticostriatal pathway)
2. The dopaminergic input (excitatory or inhibitory) from _____ _____ _____ _____ (nigrostriatal pathway)

A
  1. cerebral cortex
  2. substantia nigra pars compacta
81
Q

The inputs are received by ______ ______ neurons in caudate and putamen

A

medium spiny

82
Q

in caudate and putamen receive inputs from the cerebral cortex, substantia nigra pars compacta (SNc), and local circuit interneurons and send the information to globus pallidus and substantia nigra pars reticulata (output sources)

A

medium spiny neurons

83
Q

Medium spiny neurons of the putamen and caudate send _____ ______ _____ to the pallidal nuclei, including the globus pallidus and the substantia nigra pars reticulata

A

inhibitory GABAergic projections

84
Q

Nerve cells in the basal ganglia form a _______ circuit

A

disinhibitory

85
Q

The main output of the basal ganglia is ______ (tonic inhibition) to prevent unwanted movement

A

inhibitory

86
Q

When medium spiny neurons (neuron A) receive signals from cortex to command movement, the pallidal neurons (neuron B) are inhibited by activation of the medium spiny neurons, resulting ________ (free from inhibition) of the thalamic neurons (neuron C) and excitation of upper motor neurons (neuron D) to initiate movement

A

disinhibition

87
Q

____ ____ of the basal ganglia activates “intended” voluntary movement

A

direct pathway

88
Q

antagonizes the activity of direct pathway to terminate voluntary movement (or suppress competing unwanted movement)

A

indirect pathway

89
Q

Dopaminergic inputs from SNc on to the striatal medium spiny neurons that make up the _____ and ____ GABAergic pathways

A

indirect ; direct

90
Q

indirect output pathway has inhibitory D2 dopamine receptors on _____ _____ ____ (D2R‐type MSNs

A

medium spiny neurons

91
Q

direct output pathway is go or stop?

A

go

92
Q

Parkinson’s disease is a hypokinetic movement disorder caused by the loss of the dopaminergic neurons in *****______ _____ _____ _____

A

substantia nigra pars compacta

93
Q

difficulty in expression of movement

A

hypokinetic

94
Q

Loss of dopaminergic input → increased indirect pathway and diminished direct pathway → more tonic inhibi􏰀on of thalamus → decreased excitation of motor cortex upper motor neurons → ____ _____ _____ *****

A

reduced voluntary movement

95
Q

hyperkinetic movement disorder
* In HD, medium spiny neurons that project to the globus pallidus external
degenerate

A

Huntington’s disease

96
Q

expression of unwanted movement

A

hyperkinetic

97
Q

Loss of inhibitory input from caudate/putamen → abnormally ac􏰀va􏰀on of globus pallidus external → diminished excitatory subthalamic output to globus pallidus internal → less tonic inhibi􏰀on of thalamus → increased excita􏰀on of motor cortex neurons → undesired choreiform (“dancelike”) movement in _____

A

HD

98
Q

what are the 2 main gray matter structures of the cerebellum

A
  1. cerebellar cortex (input zone)
  2. deep cerebellar nuclei (output zone)
99
Q

The connections between the cerebellum and other parts of the nervous system are
made by three large axonal pathways

A

cerebellar peduncles

100
Q

what is the function of the cerebellum

A

correct motor errors for coordination of ongoing movement

101
Q

lateral part
— Receives input INDIRECTLY from the
cerebral cortex via pontine nuclei
— Concerned with planning and execution of spatial and temporal sequences of highly skilled movements

A

cerebrocerebellum

102
Q

median/paramedian zone
— Receives input directly from spinal cord
and brainstem
— Paramedian part is concerned with movements of distal muscles, and the median strip along the midline, called VERMIS, is concerned with movements of proximal muscles

A

spinocerebellum

103
Q

comprises two caudal‐inferior lobes, FLOCCULUS and NODULUS
— Received input from vestibular nuclei
— Concerned with vestibulo‐ocular reflex and the regulation of movements that maintain posture and balance

A

vestibulocerebellum

104
Q

an afferent pathway
— Comprises axons from neurons in the contralateral pontine nuclei of the pons

A

middle cerebellar peduncle o

105
Q

an efferent pathway
— Comprises axons from neurons in the deep cerebellar nuclei projecting to upper motor neurons in cortex (through thalamic relay) and in superior colliculus of brainstem

A

superior cerebellar peduncle

106
Q

contains both afferent and efferent pathways
— Afferent pathways include axons from the vestibular nuclei, the spinal cord, and several brainstem nuclei
— Efferent pathways are axons from deep cerebellar nuclei projecting to vestibular nuclei and reticular formation

A

inferior cerebellar peduncle

107
Q

what are the 3 deep cerebellar nuclei?

A

dentate nucleus, 2 interposed nuclei, and fastigial nucleus

108
Q

cerebral cortex provides inputs to ______

A

cerebrocerebellum

109
Q

Cortical axons do not project directly to cerebellum but synapse on neurons in the ____ nuclei on the same side first

A

pontine nuclei

110
Q

Pontine nuclei neurons project their axons to cross the ______ and enter the contralateral cerebrocerebellum via the middle cerebellar peduncle

A

midline

111
Q

Sensory pathways of axons from vestibular nuclei project to

A

vestibulocerebellum

112
Q

Proprioceptive sensory pathways project to the ______

A

spinocerebellum

113
Q

stroke in the right cerebrocortex where would it be effected

A

left

114
Q

stroke in the right cerebellum where would it be effected

A

right

115
Q

is concerned with ipsilateral representation***

A

cerebellum

116
Q

concerned with contralateral representation***

A

cerebral cortex

117
Q

what would happen if there pt has a stroke affected in the inferior olive

A

motor + learning affected

118
Q

Cerebrocerebellar pathways from dentate nucleus deal with ____ ____ _____

A

planning voluntary movements

119
Q

Spinocerebellar pathways are directed toward upper motor neurons that govern the execution of ____

A

movement

120
Q

voluntary movements of limbs

A

interposed nuclei

121
Q

axial and proximal limb muscle movement

A

fastigial nuclei

122
Q

what is the pathway for planning of movement

A

sensory cortex –> cerebrocerebellum –> dentate nucleus –> premotor cortex –> planning of movement

123
Q

what is the pathway for execution of distal muscle movement

A

proprioception form brainstem/ spinal cord –> spinocerebellum –> interposed nuclei –> primary motor cortex –> execution of distal muscle movement

124
Q

what is the pathway for the execution of axial and proximal muscle movement

A

proprioception from brainstem/spinal cord –> spinocerebellum –> fastigial nucleus –> brainstem nuclei (superior colliculus and reticular formation) –> execution of axial and proximal muscle movement

125
Q

pathway for Movement of eyes, head, and neck

A

Vestibular sensory signal (Otolith or semicircular) –> vestibulocerebellum—> vestibularnuclei –> Movement of eyes, head, and neck

126
Q

All input sources to cerebellum are received by ___ cell in the cerebellar cortex

A

purkinje cell

127
Q

Axons from the main input sources (pontine nuclei, brainstem, spinal cord) are called

A

mossy fibers

128
Q

convey main inputs

A

parallel fibers

129
Q

convey modulatory inputs

A

climbing fibers

130
Q

Purkinje cells are GABAergic so the output of cerebellar cortex is ______ (form cortical inhibitory loop)

A

inhibitory

131
Q

Deep cerebellar nuclei neurons also receive excitatory inputs from collaterals of mossy fibers, which form the ____ ____ loop

A

deep excitatory

132
Q

Function for the ____ ____ pathway is to correct motor errors for ongoing movements

A

parallel pathway

133
Q

Function for the _____ _____ pathway is to encode motor learning and memory

A

climbing fiber

134
Q

Cerebellar damage causes difficulty producing smooth, well‐coordinated, multi‐jointed movements, referred to as ____ ____

A

cerebellar ataxia

135
Q
  1. Formation of the primordial nervous system:
    gastrulation, neural induction and neurulation
  2. Initial formation of the major brain regions:
    segmentation and patterning
  3. Generation of neurons from undifferentiated precursors or stem cells: neurogenesis
  4. Migration of neurons from sites of generation to their final positions
A

events for early brain development

136
Q

Generation of neurons from undifferentiated precursors or stem cells

A

neurogenesis

137
Q

Initial formation of the major brain regions _____ _____

A

segmentation and patterning

138
Q

the single‐layered blastula is reorganized into a multilayered structure known as the gastrula

A

gastrulation

139
Q

epiblasts migrate through the primitive streak to
form the three germ layers (ectoderm, mesoderm and endoderm)

A

Epithelial‐mesenchymal transition

140
Q

nerve tissues

A

ectoderm

141
Q

the folding process of ectoderm to develop the neural tube, including formation of notochord, induction of neuroectoderm and neural plate, and transformation of the neural plate into the neural tube

A

neurulation

142
Q

____ ____cell gives rise to sensory and autonomic ganglia (the PNS)

A

neural crest

143
Q

Neuroectodermal precursor cells neural tube ____ ____ cells, which have the ability to produce the full range of cell classes in mature nervous tissues, including neurons, astrocytes, and oligodendroglial cells

A

neural stem

143
Q

The lateral margins of the neural plate fold inward, transforming the neural plate into a _____

A

tube

144
Q

The cells at the ventral and dorsal midline of the neural tube differentiate respectively into specialized strips of neuroepithelial cells called the ______ and the _____

A

floor plate and roof plate

145
Q

the floorplate and roofplate are transient structures that provide instructive signals to the developing neural tube: these structures are referred to as the _____

A

organizers

146
Q

Microglia are derived from hematopoietic stem cells but NOT neural stem cells

t/f

A

t

147
Q

pathway for neurulation

A

notochord formation –> induction of neuroectoderm + formation of neural plate –> folding of neural plate form the neural tube and specification of neural crest

148
Q

continue to expand to give rise to the forebrain and midbrain

A

anterior neural fold

149
Q

(hindbrain) becomes the medulla, pon, and cerebellum

A

Rhombencephalon

150
Q

neural tube adjacent to the ____ becomes the spinal cord

A

somites

151
Q

are specified by a BMP gradient at the dorsalmost limit of the neural tube and migrate away from the neural tube

A

neural crest cells

152
Q

give rise to a variety of progeny, including neurons and glia of the sensory and autonomic (visceral motor) ganglia, neurons of the enteric nervous system

A

neural crest cells

DRG NEURONS AND SCHWANN CELLS IN PNS

153
Q

neural tubes undergo a series of morphogenic movements that bend, fold, constrict the tube to organize into repeating units (segments) called _____

A

neruomeres

segmentation

154
Q

cerebral cortex, hippocampus, basal ganglia

A

telencephalon (Prosencephalon)

155
Q

thalamus and hypothalamus

A

diencephalon (Prosencephalon)

156
Q

midbrain tegmentum, superior and inferior colliculi

A

Mesencephalon

157
Q

The segmentation process of the neural tube in the developing brain is controlled by sequential expression of genes which encode ____ ____

A

transcription factor

158
Q

Segmentation of hindbrain and spinal cord in human is controlled by expression of Hox genes (a subset of homeotic genes) which encode _____ _____ _____

A

homeobox transcription factors*** — deals with segmentation

158
Q

Sources of inductive signals for the induction and patterning of the nervous system

A

1) notochord
(2) floorplate
(3) roofplate
(4) neuroectoderm itself
(5) adjacent mesodermal tissues such as somites

159
Q

molecules able to cause or determine morphogenesis

A

morphogens

160
Q

the signals DOES NOT have graded effects t/f

A

false it does in some cases

161
Q

signals drives cellular
differentiation, regulating the transitions between various classes of neural stem cells up to their terminal division for neurogenesis

*nuclear receptors

A

Retinoic acid

162
Q

___ ___ ___ modulate precursor cell proliferation and
differentiation

A

fibroblast growth factor

163
Q

FGFs are from ectoderm t/f

A

f from mesoderm

164
Q

___ ____ ____ play roles in the initial specification of the neural plate (neural induction) and the subsequent differentiation of the dorsal part

-act as dorsalizing signals

A

bone morphogenic proteins (BMPs)

165
Q

noggin chordin function

A

secreted from notochord and block BMP4 signaling

166
Q

regulates cell movements for lengthening the neural plate and neural tube

A

Noncanonical pathway (a.k.a. planar cell polarity pathway)

167
Q

influences precursor cell proliferation, adhesion, and differentiation

A

canonical pathway

168
Q

can activate two distinct signaling pathways, the “canonical” and “noncanonical” pathways

A

Wnt ligands

169
Q

if a baby had sonic hedgehog what can the baby not form

A

cerebral cortex, hippocampus, basal ganglia, thalamus, and hypothalamus (prosencephalon)

170
Q

Mutations of Shh cause____ (failure of the prosencephalon to divide into two cerebral hemispheres)

A

holoprosencephaly

171
Q

Precursor cells are located in the _____ _____ : the inner most cell layer surrounding the lumen of the neural tube, and a region of extraordinary proliferative activity during neural development

A

ventricular zone

172
Q

Formation of either new stem cells (self‐renew)

A

postmitotic neuroblasts

173
Q

New stem cells arise from ______ _____ of neuroectodermal cells (slow division, self‐renew)

A

symmetric divisions

174
Q

Postmitotic neurons are generated from ____ ____ progenitors (transit amplifying cells) that are molecularly distinct from slowly diving radial glial stem cells

A

asymmetrically diving

175
Q

_____ of a neuron: the time when a precursor/progenitor cell undergoes the final cell division and generates a neuroblast

A

Birthdate

176
Q

In the cerebral cortex, most neurons of the six cortical layers are generated in an _____ ____ ___

A

inside‐out manner

177
Q

the firstborn cells are eventually located in the deepest layers (layer 6) and later born neurons migrate radially, traveling through the older cells and coming to lie superficial to them (located in more superficial layers)

A

Inside‐out manner

178
Q

Interaction of cell surface ligands, the _____

A

Interaction of cell surface ligands, the Deltas

179
Q

cell surface receptors —
are key regulators of neural stem cell decisions to generate either additional stem cells or postmitotic neurons

A

notches

180
Q

down‐regulate expression of ____ ____ ____ ____ involved in the terminal differentiation of neural cells

A

bHLH neurogenic transcription factors

181
Q

In Delta‐upregulated cell, expression of bHLH neurogenic transcription factors is also upregulated and this cell differentiates to become _____

A

neuroblast

182
Q

The neighboring cells, which have Notch activated, downregulate bHLH neurogenic transcription factors and remain as ____ cells or ____ cells

A

stem or precursor

183
Q

by Delta‐Notch results in “salt and pepper” developmental pattern

-by Delta‐Notch signaling determines generation of neuroblasts

A

lateral inhibition

184
Q

Two kinds of signals mediate neuronal diversity or glial fate

A

(1) diffusible inductive signals and (2) local cell‐cell interaction signal; these signals specify cell identify by inducing of transcriptional code in each cell

185
Q

Neuronal differentiation is based primarily on local ____ ____ ___ (lateral inhibition of Delta‐Notch signal) followed by distinct histories of transcriptional regulation via a “___” of transcription factors expressed in each cell, specified either by ____ (e.g.: BMP and SHH signals) and ____ ___ ___ ___ (e.g.: Delta‐Notch signal)

A

cell‐cell interactions; code; diffusible; local cell‐cell signals

186
Q

Different ____ _______ factors have emerged as central factors for subsequent differentiation of distinct neural or glial fates

A

bHLH transcription

187
Q

____ ____ ____ of neural crest cells at distinct anterior‐posterior locations in the neural tube; is reflected in their final locations in different parts of the body

A

initial positional identity

188
Q

All neural crest cells begin as neuroepithelial cells and must undergo an
____ ____ ___ transition to downregulate expression of the adhesive genes before migration

A

epithelial‐to‐mesenchymal

189
Q

what are the neural crest cells in PNS

A

-enteric ganglia
-DRG
-sympathetic ganglia

190
Q

are specified by a BMP gradient at the dorsalmost limit of the neural tube and migrate away from the neural tube

A

neural crest cells

191
Q

Neural crest cells give rise to a variety of progeny, including neurons and glia of the ____ and ____ (visceral motor) ganglia

A

sensory + autonomic

192
Q

the final fates of the neural crest cells are critically dependent on their proper exit (____ ____ ___) + heir subsequent proper migration through terrain that provides _____ and _____ signals

A

initial positional identity; instructive; trophic signals

193
Q

minority of neurons (most of them are interneurons) and glial cells in the CNS use existing axon pathways as migratory guides

***GABAergic interneurons

A

Tangential migration

194
Q

The most prominent form of neuroblast migration in CNS is that guided by following the long processes of ___ ____ ___

A

radial glial cells

195
Q

___ ___ ___ have two major functions in the developing CNS: (1) acting as migratory guides; (2) they are neuronal progenitor (stem) cells in the developing cortex

A

Radial glial cells

196
Q

(cortical projection neurons)

A

radial migration

197
Q

Forebrain interneurons are generated in the basal forebrain and migrate ______ into dorsal structures

A

tangentially

198
Q

influence the detachment of neurons from the radial glia

A

reelin

neurobio (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions