myelin

[ mahy-uh-lin ]

Phonetic (Standard)IPA

noun

, Biology.

a soft, white, fatty material in the membrane of Schwann cells and certain neuroglial cells: the substance of the myelin sheath.

myelin

/ ˈmaɪɪlɪn; ˈmaɪɪˌliːn /

a white tissue forming an insulating sheath ( myelin sheath ) around certain nerve fibres. Damage to the myelin sheath causes neurological disease, as in multiple sclerosis

myelin

/ mī′ə-lĭn /

A whitish, fatty substance that forms a sheath around many vertebrate nerve fibers. Myelin insulates the nerves and permits the rapid transmission of nerve impulses. The white matter of the brain is composed of nerve fibers covered in myelin.

Origin of myelin¹

First recorded in 1865–70; myel- + -in ²

In MS, the amount and quality of myelin is abnormal, replaced by “sclerotic” plaques, the hallmark of the disease.

This loss of usable myelin results in poor nerve-to-nerve coordination, resulting is a slightly haywire main dashboard.

Between the neurolemma and the axis cylinder is the medullated sheath, composed of a fatty substance known as myelin.

Alveolar cells commonly contain fat-droplets and, less frequently, myelin globules.

April 18, 2024petrichor

[pet-ri-kawr]

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