Table of Contents
Where is myelin formed?
Myelin is formed in the PNS (peripheral nervous system) and CNS by the innermost sheet-like glial process in contact with the axon spiraling around it and spinning out multiple layers of overlapping membrane.
When does myelin develop?
Myelination (the coating or covering of axons with myelin) begins around birth and is most rapid in the first 2 years but continues perhaps as late as 30 years of age. Synaptic development is a more complicated issue.
What stimulates myelin production?
High-fat diet in combination with exercise training increases myelin protein expression. PLP and MBP levels were highest in the group that exercised and consumed a high-fat diet. Exercise training or high fat consumption alone also increased PLP.
How is myelin produced quizlet?
How does myelin production in CNS differ than in PNS? It is formed by oligodendrocytes in CNS and by Schwann cells in PNS, PNS= a Schwann cell spirals repeatedly around a single nerve fiber, laying down up to 1– compact layers of its own membrane with almost no cytoplasm between the membranes.
How does myelin production in the CNS differ from that in the PNS?
In CNS (central nervous system) oligodendrocyte is responsible for myelination of neuronal axons. In PNS (peripheral nervous system) myelin sheath is formed by Schwann cell. in contrast to oligodendrocyte, one Schwann cell provide myelination for one axon (actually only a segment of one axon).
What causes myelin damage?
Inflammation is the most common cause of myelin damage. Other causes include: certain viral infections. metabolic problems.
What is the function of myelin in the central nervous system?
Oligodendrocytes generate multiple layers of myelin membrane around axons of the central nervous system to enable fast and efficient nerve conduction. Until recently, saltatory nerve conduction was considered the only purpose of myelin, but it is now clear that myelin has more functions.
Where is myelin produced in the human body?
In the nerves outside of the brain and spinal cord, myelin is produced by support cells called Schwann cells. The nuclei of the Schwann cells are shown here in pink.
How does myelin wrap around the axons of neurons?
Made of lipids and proteins, myelin was later found to wrap around the axons of neurons. Myelin is made by two different types of support cells. In the central nervous system (CNS) — the brain and spinal cord — cells called oligodendrocytes wrap their branch-like extensions around axons to create a myelin sheath.
How is the myelin sheath created in the PNS?
For the myelin sheath to be created by Schwann cells in the PNS, the plasma membrane of these cells needs to wrap itself around the axons of the neuron concentrically, spiralling to add membrane layers. This plasma membrane contains high levels of fat which is essential for the construction of myelin sheath.