Development of PNS

Question 1

4th somite and above (superiorly)

Answer 1

brain

Question 2

below 4th somite (5th…) (inferiorly)

Answer 2

spinal cord

Question 3

Gray Matter

Answer 3

location of the cell bodies of the neurons that make the H shape in the spinal cord; they are not myelinated

Question 4

Dorsal or posterior horn

Answer 4

sensory (afferent neurons)

Question 5

Lateral horns

Answer 5

autonomics; only T1-L2

Question 6

Anterior or ventral horns

Answer 6

motor (efferent nuerons)

Question 7

White Matter

Answer 7

Mainly myelinated axons surrounding the H

Question 8

Dorsal or posterior funiculus

Answer 8

sensory axons

Question 9

Lateral funiculus

Answer 9

sensory and motor axons

Question 10

Ventral or anterior funiculus

Answer 10

primarily motor axons

Question 11

Alar Plate

Answer 11

Sensory neurons that stay completely in CNS

Question 12

Basal Plate

Answer 12

motor neurons in skeletal muscle and pre-synaptic neurons for autonomics

Question 13

Sulcus limitans

Answer 13

separates the Alar and Basal plate

Question 14

Ventricular zone

Answer 14

right next to neural canal; stem cells can give rise to other cells to migrate up to intermediate zoneor stay and give rise to epindymoblast and then ependymal cells which will line ventricles and central canal

Question 15

choroid plexus cell

Answer 15

makes CSF; comes from epindymoblast

Question 16

Intermediate zone

Answer 16

stem cells that migrate in and form neurons, astrocytes (structural), and other cells; gray matter

Question 17

Marginal zone

Answer 17

Axons that are myelinated; oligodendrocytes in CNS and Schwann cells in PNS

Question 18

Arising from neural tube (neuroectoderm)

Answer 18

dendrites, astrocytes, oligodendrocyte, and the choroid plexus

Question 19

Microglial cells

Answer 19

arise from mesoderm; monocytes of brain and spinal cord (macrophages)

Question 20

Position of spinal cord in newborns

Answer 20

L2 or L3; must go lower for puncture

Question 21

position of spinal cord in adults

Answer 21

L1 or L2

Question 22

Give rise to spinal ganglion cells and sensory neurons in periphery

Answer 22

neural crest cells

Question 23

How to make alar plate

Answer 23

high BMP from roof plate and surface ectoderm activate PAX3 and PAX7; DORSAL

Question 24

how to make basal plate

Answer 24

High Shh from notochord and floor plate activated NKX2.2k and NKX6.1; VENTRALLY

Question 25

how to make ventral motor neurons

Answer 25

slightly less Shh and slightly more BMP activates NKX6.1 and PAX6

Question 26

GSE

Answer 26

General somatic efferent; motor neurons for muscle from somites; from NEUROECTODERM

Question 27

GVE

Answer 27

General visceral efferent; autonomic motor neurons to smooth and cardiac muscle; from NEUROECTODERM

Question 28

SVE

Answer 28

Special (brachial) visceral efferent; motor neurons for muscles derived from pharyngeal arches; from NEUROECTODERM

Question 29

GSA

Answer 29

General somatic afferent; sensory neurons in skin, joint capsules, tendons, muscles; from ectoderm or adjacent to ectoderm; NEURAL CREST DERIVED

Question 30

GVA

Answer 30

General visceral afferent; sensory neurons from endoderm or mesoderm derived adjacent to endoderm; organs; NEURAL CREST DERIVED

Question 31

SSA

Answer 31

Special somatic afferent; hearing, balancing, and sight

Question 32

SVA

Answer 32

Special visceral afferent; taste and smell

Question 33

short, myelinated fibers derived from neuroectoderm

Answer 33

Pre-ganglionic cells from spinal cord of sympathetic NS

Question 34

longer, not myelinated fibers derived from neural crest

Answer 34

post-ganglionic cells from spinal cord of sympathetic NS

Question 35

long myelinated from neuroectoderm

Answer 35

pre-ganglionic of parasympathetic

Question 36

short not myelinated from neural crest

Answer 36

post-ganglionic of parasympathetic; found in walls of the organ

Question 37

sources of PNS

Answer 37

neural crest and ectodermal placodes

Question 38

cranial nerves that parasympathetic travel on

Answer 38

3,7,9, and 10

Question 39

sacral nerves for parasympathetic

Answer 39

S2, 3, and 4

Question 40

when does the CNS become myelinated

Answer 40

6th month through puberty; from neuroectoderm

Question 41

PNS myelination timeline

Answer 41

4th month in utero when baby kicks; motor before sensory; SCHWANN cells; from neural crest