Myelination and Gray/White Matter

Question 1

a fatty (lipid and protein) covering that forms around the axon

Answer 1

myelination

Question 2

What does myelination do?

Answer 2

increases the speed/propagation of action potentials

Question 3

“sheath of schwann”

Answer 3

neurilemma aka neurolemma

Question 4

What is a neurilemma?

Answer 4

“sheath of schwann” that acts as insulation for the axon of the neuron

Question 5

nodes of Ranvier

Answer 5

myelin sheath gaps

Question 6

gaps in the myelin sheath where the axon is bare, no insulation

Answer 6

myelin sheath gaps aka nodes of Ranvier

Question 7

Mostly cells bodies, no myelination

Answer 7

gray matter

Question 8

What is the lack of myelination in gray matter mostly due to?

Answer 8

chromatophilic substance

Question 9

What is white matter?

Answer 9

axons aka nerve fibers are myelinated forming a white fatty sheath

Question 10

How is gray and white matter organized in the spinal cord?

Answer 10

gray butterfly shaped area surrounded by white matter

Question 11

How is gray and white matter organized in the brain?

Answer 11

cortex (bark of tree) of gray matter that surrounds white matter with pockets of gray matter (nuclei)