7.2 - Lab - Nerve

Question 1

Meissner’s Corpuscle

Answer 1

• transduce sensation of light touch

- positioned in CT as close as possible to the epithelium

Question 2

Pacinian corpuscles

Answer 2

• designed to transduce pressure and vibration
• found deep in tissue - in the hypodermal (Adipose) layer far from the epithelial surface
• nerve ending is sheilded by several layers of specialized cells from the surrounding CT

Question 3

Dorsal Root Ganglion

Answer 3

• location of the cell bodies of primary sensory neurons
• found within the vertebral column at point where nerve roots enter and exit the spinal cord
• one on each side of the body

Question 4

White matter in the spinal cord

Answer 4

= ascending and descending axons

Question 5

Canonical features of neurons

Answer 5

• large euchromatic nucleus + a small dense nucleolus

- cell bodies of sensory neurons are the largest cells present (because they have to support such a long axon)

Question 6

Satellite cells

Answer 6

• present in the DRG

- supporting cells (appear as smaller cell bodies) for the soma of the sensory neurons in the DRG

Question 7

Ventral Root

Answer 7

• where motor neurons exit spinal cord

- have their cell bodies located in the grey matter of the spinal cord

Question 8

Silver Stain Method

Answer 8

• stains cell bodies, axons, and dendrites

Question 9

Nissl Technique

Answer 9

• stains the ER + ribosomes? in neurons
• will not be seen in the axon at all
• will be seen heavily in the soma and partially in dendritic process

Question 10

Myelin sheath appearance in H and E preparation

Answer 10

• white space because of the mostly dissolved lipid that makes it up

Question 11

Perineurium

Answer 11

• dense CT covering a nerve fiber

- often a crucial clue in identifying nervous tissue

Question 12

Endoneurium

Answer 12

• CT immediately surrounding the axons

Question 13

Epineurium

Answer 13

• CT adventitial to the perineurium

Question 14

What are the terms used to describe a cluster of cell bodies in the CNS and PNS

Answer 14

CNS = nuclei
PNS = ganglion

Question 15

What are the terms used to describe the group of axons in the CNS and PNS

Answer 15

CNS = tract
PNS = Nerve

Question 16

What are the terms used to describe the glia in the CNS and PNS

Answer 16

CNS - Microglia, Macroglia (Astrocytes + oligodendrocytes)

PNS - Schwann Cells + Satellite cell (subdivision of schwann cell in the DRG that support the cell bodies)