Lec 14 Structure and Development of the NS Flashcards
1
Q
What is the cerebrum composed of?
A
two hemispheres
2
Q
What does each hemisphere do?
A
receives input from and controls movement on the contralateral side
3
Q
What does contralateral mean?
A
opposite
4
Q
Describe the cerebellum
A
Has as many neurons as the cerebrum with connections to the cerebrum and spinal cord
5
Q
What does the cerebellum do?
A
Receives input and controls movement on the ipsilateral side
6
Q
Define ipsilateral
A
same
7
Q
What is the purpose of the brain stem?
A
It is the relay center. It’s primitive but essential for life
8
Q
What does the brain stem do?
A
regulates body temperature, breathing and consciousness
9
Q
What is the spinal cord?
A
Structure enclosed in vertebral column
10
Q
Is the spinal cord part of the CNS or the PNS?
A
PNS
11
Q
What is pyramidal decussation?
A
point of meeting for the medulla and spinal cord.
12
Q
How do motor fibers travel down the nervous system after meeting the pyramidal decussation?
A
Motor fibers move from medullary pyramids cross midline. They continue into the spinal cord, merging as part of the corticospinal tract
13
Q
What is the purpose of pyramidal decussation?
A
The left and right cortical hemispheres control muscles on the contralateral) side of the body
14
Q
What does anterior mean?
A
front
15
Q
What is another way to say anterior?
A
rostral
16
Q
What does rostral mean?
A
front
17
Q
What does posterior mean?
A
back
18
Q
What is another way to say posterior?
A
caudal
19
Q
What does caudal mean?
A
back
20
Q
What does lateral mean?
A
side
21
Q
What does medial mean?
A
middle
22
Q
What does dorsal meal?
A
top/back
23
Q
What does ventral mean?
A
bottom/belly
24
Q
What does superior mean?
A
located above another structure
25
What does inferior mean?
located below another structure
26
What does superficial mean?
close to the surface
27
What does deep mean?
further from the surface
28
Describe what sagittal sectioning looks like for the brain
longer ends of paper go up and down, slicing from the middle
29
What does coronal sectioning looks like for the brain
longer ends of paper go left and right, slicing from the middle
30
What is another name for coronal (concerning section planes)?
transversal
31
What does horizontal sectioning look like for the brain?
shorter ends of paper face in front of you and towards you, slicing flat in the middle of the brain
32
When can you see bilateral symmetry while sectioning the brain?
with coronal sectioning (produces symmetrical results)
33
What is the brain the evolutionary expansion of?
The neocortex
34
What is the neocortex?
part of the cerebral cortex where it is thought the higher cognitive processes come from
35
How do cerebral hemispheres affect the brain's appearance?
Since it is such a large part of the brain, it overtakes the appearance of the brain
36
What are gyri?
Ridges of the brain
37
What are sulci?
Groves of the brain
38
What are the main focal parts for the sulci? (3, named sulcus)
Central Sulcus
Lateral Sulcus/Sylvian Fissure
Parieto-Occipital Sulcus
39
What is a fissure?
Something that is deeper than sulci to create large divisions
40
What areas indicate fiscal structures in the brain? (2)
Longitudinal
Transverse
41
What is the purpose of transversal fissures?
They separate the cerebrum from
cerebellum
42
What is the purpose of longitudinal fissures?
They separate the left and right
hemispheres
43
What is grey matter?
Cell bodies of neurons
44
What area of the brain holds the most grey matter?
The cortex
45
What is white matter?
Myelinated axons
46
What is a nucleus (structurally)?
A mass of neurons that rest deep inside of the brain
47
Dorsal roots are _____
sensory
48
Ventral roots are _____
motor
49
In the CNS, Dorsal and Ventral roots of the spinal core are myelinated by ______ and protected by _____
Oligodendrocytes; Meninges
50
Once Dorsal and Ventral roots are in the PNS, ______ ______ take over both functions
Schwann Cells
51
the PNS has two nervous systems:
Somatic and Autonomic
52
The Somatic Nervous system controls ______ behaviors
voluntary
53
What is another name for Autonomic Nervous System?
The Visceral Nervous System
54
What does the Autonomic Nervous System control?
Involuntary behaviors
55
Where does the Somatic Nervous System oversee in the nervous system?
CNS: Cell body of motor neurons
PNS: axons
56
What portion of the nervous system does the Autonomic Nervous System control?
that which supplies the motor innervation to structures that are involuntary
57
What is the motor function of the Autonomic Nervous System?
mostly smooth muscle (blood vessels and skin), heart muscle and glands
58
The sympathetic and parasympathetic subdivisions of the autonomic divisions of the PNS emanate from _____ _____
distinct regions
59
Define ganglion
a collection of neuron cell bodies (somas) in the PNS
60
Define somas
neuron cell bodies
61
What is an example of ganglion?
dorsal root ganglia
62
What does dorsal root ganglia contain?
cell bodies of sensory neurons
63
Where do preganglionic neurons from the sympathetic nervous system emanate from?
spinal cord; thoracic and anterior lumbar regions
64
Where do preganglionic neurons from the parasympathetic nervous system emanate from?
cranial nerves at the anterior end and sacral regions in the posterior end
65
What neurotransmitter is most prominent in the Sympathetic nervous system?
Norepinephrine
66
What neurotransmitter is most prominent in the Parasympathetic nervous system?
ACh (acetylcholine)
67
What does the autonomic division of the PNS control?
blood pressure using heart rate and blood vessels, contraction and relaxation of smooth muscle, dilate/constrict pupils and stimulate/inhibit digestion
68
Where does the PNS autonomic division control?
your heart, smooth muscle, pupils and digestion system
69
How many cranial nerves are there?
12
70
Who created the cranial nerve system?
Galen
71
Where do cranial nerves originate from?
brain stem, cerebrum, innervate the head
72
Are cranial nerves part of the CNS or PNS?
Both. Some are CNS (somas) but mostly PNS (axons)
73
What are cranial nerves for?
They can be sensory, motor or both
74
Where do cranial nerves send information?
From the brain to regions of your head, neck and GI track
75
What develops on days 2-10 for neurodevelopment?
Cleavage to blastocyst
76
What develops on days 11-15 for neurodevelopment?
Gastrulation, neural induction, and formation of three primary "germ" layers
77
What develops on days 16-25 for neurodevelopment?
Neuralation and formation of the neural tube
78
What develops on days 26 and up for neurodevelopment?
Organogenesis and brain "patterning"
79
Describe Neural Induction
occurs during gastrulation (days 11-15)
80
What occurs before Neural induction?
Blastulation
81
Describe Blastulation
begins source of ES cells
82
What is gastrulation?
When the mesoderm is formed as cells of the embryo move
83
What does the mesoderm do?
induce overlying neuroectoderm to become neural fate
84
What is the neural inducer and what does it do?
It's called noggin and inhibits BMP4
85
Describe the outcome for neural tube formation:
the neural tube becomes brain and spinal cord; then forms a neural crest which is an offshoot closure for the neural tube
86
What is neural tube formation called?
Neurulation
87
What does the neural crest form?
sensory and autonomic neurons, neuroendocrine cells, glia and melanocytes
88
What patterning does regionalization develop in regards to neurodevelopment?
Anterior-Posterior patterning (AP)
Dorsal-Ventral patterning (DV)
89
What does Anterior-Posterior patterning form?
the forebrain, midbrain, hindbrain, and spinal cord
90
What does Dorsal-Ventral patterning determine?
Ventral and Dorsal cell types (ex: tegmentum vs. tectum)
91
What does neurogenesis indicate?
Proliferation/Migration/Differentiation
92
What are the six major stages of neurodevelopment?
1. Neural induction
2. Neural tube formation
3. Regionalization/Patterning
4. Neurogenesis
5. Axonal pathfinding/Synaptogenesis
6. Target-dependent cell death/Synaptic pruning
93
What is the ectoderm in regards to neural induction?
Nervous system and skin cells
94
What is the endoderm in regards to neural induction?
Internal organ cells
95
What is the mesoderm in regards to neural induction?
Muscle and skeleton cells
96
What does noggin do?
Produces neural inducers by the mesoderm
97
What is noggin, chordin and follistatin in regards to neural inducers?
proteins which are encoded by genes
98
What happens to the neuroectoderm if there are no neural inducers?
The neuroectoderm would become epidermis instead of neural tissue
99
How are neural inducers used today in research?
They help convert ES of iPS stem cells into neurons (observed in culture)
100
What are neural inducer molecules called?
morphogens
101
