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myelin sheath

noun

Anatomy.
  1. a wrapping of myelin around certain nerve axons, serving as an electrical insulator that speeds nerve impulses to muscles and other effectors.


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Word History and Origins

Origin of myelin sheath1

First recorded in 1895–1900
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Example Sentences

Examples have not been reviewed.

However, EBV infection has been linked to several diseases, including MS: an incurable, chronic autoimmune disease that causes the body's immune system to attack the myelin sheath of neurons in the brain and nervous system.

These useful cells in the brain, called oligodendrocytes, are responsible for producing myelin sheaths that wrap around cable-like parts of nerve cells called axons, much like the plastic insulation around a wire.

For example, in vertebrates, the researchers found genes critical for the formation of myelin sheaths around nerve cells, which are essential for fast nerve signal transmission.

In the brain, oligodendrocytes wrap around the long, skinny connections between nerve cells known as axons, where they produce a lipid membrane called a myelin sheath that coats the axon.

The thicker this myelin sheath, the faster the transmission.

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myelinationmyelitis