Lecture 16: Peripheral Nervous System Flashcards Preview

Year 1: 03. MSK Exam 1 > Lecture 16: Peripheral Nervous System > Flashcards

Flashcards in Lecture 16: Peripheral Nervous System Deck (44)
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1

Where (in terms of somites) does the divison between Brain and Spinal Cord occur?

Brain is 4th Somite and Superior

Spinal Cord is Inferior to the 4th Somite

2

What is grey matter mostly made of?

Unmyelinated cell bodies

3

What is White Matter mostly made of?

Myelinated Axons

4

What region of the spine contains the Lateral Horns?

T1 to L2

(absent in most of the spine)

5

What is the dorsal part of the Spinal Cord (grey and white matter) primarily responsible for?

Sensory input

6

Before the Epiblast invaginates, is the region of the Alar Plate medial or lateral to the region of the Basal Plate of the future Neural Tube?

Lateral -The Alar Plate will be on top of the Basal Plate in the Neural Tube

7

What is found in the Alar Plate of the Neural Tube?

 Sensory Neurons that never leave the Central Nervous System

8

Where do the Sensory Neurons of the Peripheral Nervous System (First Order Neurons) come from?

The Neural Crest

9

What comes from the Basal Plate of the Neural Tube?

Motor Neurons

10

What separates the afferent from the efferent nerves in the Neural Tube?

The Sulcus Limitans

11

What is the name for the center space in the Neural Tube?

Central Canal

12

What does the Intermediate Zone of the early Spinal Cord become?

Gray Matter

13

What does the Marginal Zone of the early Spinal Cord become?

White Matter

14

What cell type does the Ventricular Zone contain?

What do these cells do within the Ventricular Zone?

Stem Cells

They become Ependymoblasts, which can then either become Ependymal Cells or Choroid Plexus Cells (which make CSF)

15

What do Ventricular Zone Stem Cells become in the Intermediate Zone of the Early Spinal Cord?

Neruons, Astrocytes (protoplasmic), Glial Cells

(and others)

16

What do Ventricular Zone Stem Cells become in the Marginal Zone of the Early Spinal Cord?

What precursor to these cells is found in the Intermediate Zone?

Oligodendrocytes, Astrocytes (fibrous)

Glioblasts

 

17

What do Schwann Cells do?

What embryological structure do they come from?

They myelinate neurons of the Peripheral Nervous System

Neural Crest

18

What do Oligodendrocytes do?

What embryological structure do they come from?

They myelinate neurons of the Central Nervous System

Neuroectoderm

19

What germ layer do Microglial Cells come from?

What do they do?

Mesoderm

They come from monocytes, which come from mesoderm

They are phagocytes

20

In an early fetus, the Vertebrae and the Spinal Cord are the same length. What causes the Spinal Cord to stop short of the Vertebrae in a newborn?

The Vertebrae grow faster than the Spinal Cord

21

Where does Keim say a newborn's Spinal Cord stops?

Where does Keim say an adult's Spinal Cord stops?

Why is this clinically relevant?

Newborn: L2-L3

Adult: L1-L2

NICU Spinal Taps are lower.

22

What embryonic structure gives rise to the Spinal Ganglion Cells

Neural Crest

23

What signal triggers early Dorsal Nerve differentiation?

What gives off this signal?

What kinds of nerves are these incited to become?

BMP

Roof Plate and Dorsal Surface Ectoderm

Sensory Nerves

24

What signal triggers early Ventral Nerve differentiation?

What releases this signal?

What kinds of nerves are these incited to become?

Sonic Hedgehog

Floor Plate and Notocordal Process of the Notocord

Motor Neurons

25

What signal triggers differentiation of the Spinal Cord into the Alar Plate?

BMP

26

What signal triggers Spinal Cord differentiation into the Basal Plate?

Sonic Hedgehog

27

What genes do high levels of BMP activate?

PAX3 and PAX7

BatMan's Pouch might be on display at PAX

28

What genes do high levels of SHH (Sonic Hedgehog) activate?

NKX2.2 and NKX6.1

"Sonic Hedgehog NKX2.2" and 6.1 sound like Sega skiing games to me

29

In the Peripheral Nervous System, what two structures come from the Neural Tube?

Pre-ganglionic Autonomic Neurons (come from the lateral horn - remember this is only present from T1 to L2)

Motor Neurons

30

Where do the Neurons of the Dorsal Root Ganglia come from?

What kind of Nerves (in terms of orientation) are they?

Neural Crest

Pseudo-Unipolar