Development of PNS Flashcards

1
Q

During what week do the PNS and CNS develop?

A

Week 3

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

Weeks 3-8 are considered what during development?

A

Critical Period

***Major abnormalities can occur here

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

T/F. Weeks 9-38 (birth) can have both major and minor abnormalities in development.

A

False. These weeks only have functional and minor abnormalities occur.

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

What are the weeks in Neural development that major abnormalities can occur and be detrimental?

A

Weeks 3-16

***Weeks after that can have minor abnormalities occur, and this development continues until age 22 when CNS myelination is complete

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

These can be used clinically in an ultrasound to age an embryo.

A

Somites

***Count the number present on the embryo

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

At the end of which week would we have a Neural Tube/

A

Week 4

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

What is included in the CNS?

A

Brain

Spinal Cord

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

What is included in the PNS?

A
Cranial Nerves
Spinal Nerves
Ganglia
Enteric Plexus 
Sensory receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the PNS divided into?

A

Somatic

Autonomic

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

(SOMATIC/AUTONOMIC) is voluntary and (SOMATIC/AUTONOMIC) is involuntary and done unconsciously.

A

Somatic
Autonomic

***Each have a sensory and motor component

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

What is the Autonomic PNS subdivided into?

A

Parasympathetic

Sympathetic

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

T/F. Parasympathetic and Sympathetic groups are sensory.

A

False. They are motor.

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

What are the types of matter the spinal cord is made up of?

A

Gray Matter

White Matter

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

This is the term for a collection of axons.

A

Funiculus

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

This is where cell bodies of neurons are located, and it has a posterior, anterior, and lateral horn.

A

Gray Matter

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

This is where axons are located and it is where the posterior, anterior, and lateral funiculus are located. It is myelinated.

A

White Matter

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

What is the sensory component of Gray Matter?

A

Dorsal (posterior) horn

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

What is the autonomic (sympathetic) component of Gray Matter?

A

Lateral horn

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

What is the motor component of Gray Matter?

A

Ventral (anterior) horn

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

What component of White Matter is only sensory and which one is sensory AND motor?

A

Dorsal (posterior) funiculus

Lateral funiculus

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

What component of the White Matter is primarily motor?

A

Ventral (anterior) funiculus

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

The Neural Tube is caudal to what?

A

Fourth pair of somites

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

This is what produces sensory neurons that stay in the brain and spinal cord.

A

Alar Plate

***Sensory neurons that go out into the periphery come from Neural Crest cells!

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

What type of germ layer is the Alar Plate?

A

Neuroectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
This gives rise to motor neurons (Brachial Plexus, etc.).
Basal Plate
26
What lies between the Alar Plate and the Basal Plate?
Sulcus limitans
27
In the formation of the spinal cord, this zone is closest to the central canal.
Ventricular zone (Zone 1)
28
In the formation of the spinal cord, this zone is what makes up the Gray Matter (cell bodies).
Intermediate zone (Zone 2)
29
In the formation of the spinal cord, this zone is what makes up the White Matter (axons).
Marginal zone (Zone 3)
30
What cells are near the Central Canal, and what is their path of development?
Germinal or ventricular cell --- Ependymoblast --- Ependymal Cell --- Choroid Plexus Cell (makes CSF)
31
What cell always lines the Central Canal?
Ependymoblasts
32
What cells would be in Zone 2 (Gray Matter)?
Germinal or ventricular cells (in Central Canal) would differentiate into ---- Immature Neurons -- become Neurons Glioblasts -- become Astrocytes and Radial Glial Cells (Also become Oligodendrocytes but those are in Zone 3)
33
What cells would be in Zone 3 (White Matter)?
Oligodendrocytes (from Glioblasts in Zone 2) ***Their function is to myelinate axons, hence their location
34
Neurons, Astrocytes, Oligodendrocytes, and Ependymal cells are all derived from what germ layer?
Neuroectoderm ***Developed from Neural Tube
35
These cells in the CNS are made from monocytes in the blood, making them mesodermal.
Mesenchymal cells
36
In the CNS, what do mesenchymal cells differentiate into?
Microglial cells
37
At what stage of development is the spinal cord and vertebral column the same length?
Third month in utero
38
At what position does the spinal cord end for a newborn and adult, respectively?
``` Newborn = L2 or L3 Adult = L1 or L2 ```
39
Explain why newborns and adults would have a different needle placement for lumbar puncture.
Newborns spinal cord ends at L2 or L3 and as they grow, their vertebral bones grow too. The spinal cord however, does not grow with the bones. Instead, as the bones grow the neurons move up and only the axons will lengthen (Cauda Equina). This is why adults spinal cord ends at L1 or L2.
40
Spinal ganglion cells and sensory neurons in the periphery are derived from what germ cell layer?
Neural crest ***Means Ectoderm and Mesoderm together
41
In the formation of the spinal cord, on the ventral side there is the Notochord and the Floor Plate which both signal _______, and on the dorsal side there is the Roof Plate and Epidermis which signal _______.
SHH | BMP
42
The release of SHH and BMP create a gradient. Which is greater ventrally and which is greater dorsally?
High SHH levels ventrally (less as it moves dorsal) High BMP levels dorsally (less as it moves ventrally) ***The varying levels throughout this gradient provide signals for many different things! ***Remember dorsal is sensory and ventral is motor!
43
High BMP levels activate ______ and ______ which give us our sensory neurons. These sensory neurons will differentiate and give us our _______ _______.
PAX3 PAX7 Alar Plate
44
High SHH levels activate ______ and ______ which give us our ventral neuron formation. These neurons give us our ______ ______.
NKX2.2 NKX6.1 Basal Plate
45
Just dorsal there are slightly lower SHH and higher levels of BMP. At this point, ______ and ______ signals are activated which give us our ventral motor neurons. Our ventral motor neurons then make up our _______ _______.
NKX6.1 PAX6 Anterior (ventral) horn
46
What two germ layers make up the PNS?
Neural Crest | Neuroectoderm
47
In the development of the PNS, cells that develop from the Neural Tube (neuroectoderm) are...
``` Motor neurons (in ventral/anterior horn) Pre-ganglionic autonomic neurons (in lateral horn) ```
48
In the development of the PNS, cells that develop from the Neural Crest are...
- Neurons of dorsal root ganglia - Sensory ganglia of cranial nerves - Schwann cells (myelinate) - Sympathetic ganglia - Parasympathetic ganglia
49
In a typical segmental nerve, the Dorsal (Posterior) Root is (MOTOR/SENSORY) and contains a Spinal ganglion (called Dorsal Root Ganglion).
Sensory
50
In a typical segmental nerve, the Ventral (Anterior) Root is (MOTOR/SENSORY).
Motor
51
In a segmental nerve, the Dorsal and Ventral Roots come together to form the ______ ______ which is a mix of sensory and motor.
Spinal Nerve
52
The Spinal Nerve then branches into what? Are they motor or sensory?
Dorsal (Posterior) Ramus Ventral (Anterior) Ramus They are mixed -- both sensory and motor
53
What does motor Dorsal Rami supply? Sensory Dorsal Rami?
Motor is to dorsal muscles | Sensory is to dorsal integument
54
What does motor Ventral Rami supply? Sensory Ventral Rami?
Motor to limbs, lateral, and ventral body wall | Sensory to integument of the same regions
55
This is autonomic and provides motor and sensory to viscera.
Ramus communicantes
56
(AFFERENT/EFFERENT) neurons are motor fibers that are derived of neuroectoderm (basal plate).
Efferent
57
(SOMATIC/VISCERAL) motor fibers end on skeletal muscle, while (SOMATIC/VISCERAL) motor fibers end on autonomic ganglion cells, which in turn control smooth muscle, cardiac muscle, and glands.
Somatic | Visceral
58
(AFFERENT/EFFERENT) neurons are sensory fibers. If they are going to the periphery then they are derived from Neural Crest.
Afferent
59
(SOMATIC/VISCERAL) sensory fibers originate chiefly from the integument and (SOMATIC/VISCERAL) sensory fibers originate from the viscera.
Somatic | Visceral
60
The ANS (Autonomic Nervous System) is involuntary and innervates the smooth muscle, cardiac muscle, and glands. It consists of two motor pathways, which are...
Sympathetic | Parasympathetic
61
In the ANS, what is formed by Neural Crest and what is formed by Neuroectoderm?
Neural Crest -- formation of ganglia and post-ganglion (post-synaptic) cells Neuroectoderm -- formation of the pre-ganglion cells (pre-synaptic) cells from lateral horn
62
Sympathetic ANS is located in the spinal cord in the thoracolumbar region from ______ to ______ in the lateral horn.
T1 | L2 (maybe L3)
63
What is the two link chain of the Sympathetic ANS?
Short and myelinated Preganglionic fiber from spinal cord to Sympathetic Ganglia (***Neuroectoderm) Long and unmyelinated Postganglionic fiber from Ganglia to Viscera (***Neural Crest)
64
These are sympathetic ganglia that lead to the head and heart.
Superior Cervical Ganglion Middle Cervical Ganglion Inferior Cervical Ganglion
65
These are "Prevertebral Ganglia", which are all sympathetic ganglia.
Celiac Ganglion Aortico-renal Ganglion Superior Mesenteric Ganglion Inferior Mesenteric Ganglion
66
Parasympathetic ANS is in the Cranial-sacral region. What Cranial Nerves and Sacral Spinal Nerves carry parasympathetic fibers (preganglionic)?
CN 3, 7, 9, 10 | Sacral Nerves 2, 3, 4
67
What is the two link chain of the Parasympathetic ANS?
Long and myelinated Preganglionic fiber from spinal cord to Parasympathetic Ganglia (***Neuroectoderm) Short and unmyelinated Postganglionic fiber from Ganglia to viscera (***Neural Crest)
68
These are Parasympathetic Ganglion that you would see in the walls of the viscera (organs).
Ciliary Ganglion Pterygopalatine Ganglion Submandibular Ganglion Otic Ganglion
69
The CNS is myelinated by _________ and the PNS is myelinated by ________.
``` Oligodendrocytes (from Neuroectoderm) Schwann Cells (from Neural Crest) ```
70
T/F. CNS myelination starts in the lower brain stem with older tracts starting first and ends with newer tracts. This lasts until age 22.
True
71
In the PNS, (MOTOR/SENSORY) roots are myelinated before (MOTOR/SENSORY) roots. Occurs during the 4th month.
Motor | Sensory