WEEK 2: HISTOLOGY OF THE SPINAL CORD.

Question 1

Describe the glial cells.

Answer 1

*Support neurons – functionally, mechanically and metabolically

*10x more glial cells than neurons

*Surround both the neuronal cell bodies, which are often larger than the glial cells, and the processes of axons and dendrites occupying the spaces between neurons.

Question 2

State the 5 types of glial cells in the CNS and their functions.

Answer 2

1.Microglia: Engulf and destroy microbes and cellular debris; function as small macrophages.

2.Oligodendrocytes: Myelin production, electrical insulation.

3.Ependymal cells: Aid in CSF production.
-Line the ventricle of the brain and central canal of the spinal cord.

4.Astrocyte: Form the BBB., Support neurons, Replicate to occupy spaces of dying neurons

5.Satellite cells: Structural and metabolic support of th neurons.

Question 3

How are Schwaan cells different from the oligodendrocytes?

Answer 3

OLIGODENDROCYTES
*Found in the CNS
*1 oligodendrocyte myelinates up to 60 neurons.
*Derivative of the neuroepithelial cells.

SCHWAAN CELLS
*Found in the PNS
*1 Schwaan cell myelinates 1 neuron at a time.
*Derivative of the neural crest

Question 4

What does white matter contain?

Answer 4

Axons and myelin producing oligodendrocytes

Very few neuronal cell, astrocytes and microglia are present.

Question 5

What does the cell body contain?

Answer 5

Neuronal cell bodies, dendrites, unmyelinated potions of axons, astrocytes and microglial cell

Question 6

The peripheral nerves consist of a lot of nerve fibers forming a bundle.

What is this bundle called?

Answer 6

Fasicle.

Question 7

Describe the following in relation to the fascicle.
*Epineurium
*Perineurium
*Endoneurium

Answer 7

1.Endoneurium covers the axon, innermost layer around each nerve fiber.

*Perineurium covers each fascicle

*Epineurium is the outermost dense connective tissue covering the bundles of fascicles and spaces between nerve fibers.