myelin


myelin
myelinic, adj.
/muy"euh lin/, n. Biol.
a soft, white, fatty material in the membrane of Schwann cells and certain neuroglial cells: the substance of the myelin sheath.
Also, myeline /muy"euh leen'/.
[1865-70; MYEL- + -IN2]

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      white, insulating sheath composed of fatty materials, protein, and water on the axon of many nerve fibres. The myelin sheath is deposited by Schwann cells in layers surrounding the nerve fibres of the central and peripheral nervous systems of many organisms. The sheath is interrupted at intervals by gaps called nodes of Ranvier; this structure speeds nerve conduction, as impulses jump from node to node in a process known as saltatory conduction.

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Universalium. 2010.

Look at other dictionaries:

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  • myelin — noun Etymology: International Scientific Vocabulary Date: 1873 a soft white somewhat fatty material that forms a thick myelin sheath about the protoplasmic core of a myelinated nerve fiber • myelinic adjective …   New Collegiate Dictionary

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