7.2 - Lab - Nerve Flashcards
Meissner’s Corpuscle
- transduce sensation of light touch
- positioned in CT as close as possible to the epithelium
Pacinian corpuscles
- 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
Dorsal Root Ganglion
- 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
White matter in the spinal cord
= ascending and descending axons
Canonical features of neurons
- 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)
Satellite cells
- present in the DRG
- supporting cells (appear as smaller cell bodies) for the soma of the sensory neurons in the DRG
Ventral Root
- where motor neurons exit spinal cord
- have their cell bodies located in the grey matter of the spinal cord
Silver Stain Method
- stains cell bodies, axons, and dendrites
Nissl Technique
- 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
Myelin sheath appearance in H and E preparation
- white space because of the mostly dissolved lipid that makes it up
Perineurium
- dense CT covering a nerve fiber
- often a crucial clue in identifying nervous tissue
Endoneurium
- CT immediately surrounding the axons
Epineurium
- CT adventitial to the perineurium
What are the terms used to describe a cluster of cell bodies in the CNS and PNS
CNS = nuclei PNS = ganglion
What are the terms used to describe the group of axons in the CNS and PNS
CNS = tract PNS = Nerve
