Myelin and Myelination Flashcards
1
Q
Myelin
A
- Lipid-rich
- Synthesised by non-neuronal cell
- Increases conduction velocity
- Loss of myelin produces neurological disorders
- Myelin may alter in learning and memory
2
Q
What percentage of dry weight of white matter is myelin?
A
50%
3
Q
Where does myelin come from in the PNS?
A
Schwann cells
4
Q
Where does myelin come from in the CNS?
A
Oligodendrocytes
5
Q
Schwann cells myelinate _____ axons
A
Individual
6
Q
Oligos myelinate ______ axons/parts of axons
A
Several
7
Q
What does myelin look like?
A
Protein - lipid - protein repeats
8
Q
What is the periodicity of myelin in the PNS?
A
11.9 nm
9
Q
What is the periodicity of myelin in the CNS?
A
10.7 nm
10
Q
What percentage of myelin is water?
A
~40%
11
Q
What percentage of myelin is dry lipid?
A
70-85%
12
Q
What percentage of myelin is protein?
A
15-30%
13
Q
What is myelin made of?
A
- Water
- Dry lipid
- Protein
14
Q
PNS has less…
A
- Cerebroside
- Sulfatide
15
Q
CNS has more…
A
Sphingomyelin