Schwann cell

Schwann cell
Schwann cell 'shwän- n a cell that forms spiral layers around a myelinated nerve fiber between two nodes of Ranvier and forms the myelin sheath consisting of the inner spiral layers from which the protoplasm has been squeezed out
Schwann 'shvän Theodor Ambrose Hubert (1810-1882)
German anatomist and physiologist. Schwann is regarded as the founder of modern histology. He is best known for his conception of the structure and function of cells: he defined the cell as the basic unit of human anatomy. Investigating the digestive processes in 1836, he isolated a substance responsible for digestion in the stomach. He named this first enzyme prepared from animal tissue pepsin. Schwann is also regarded as a founder of the germ theory of putrefaction and fermentation. He was the first to investigate the laws of muscular contraction by physical and mathematical methods and to demonstrate that the tension of a contracting muscle varies with its length. In 1838 he published his description of the myelin sheath covering peripheral axons. He also formulated a basic principle of embryology by observing that the egg is a single cell that eventually develops into a complete organism.

* * *

any of the large nucleated cells whose cell membrane spirally enwraps the axons of myelinated peripheral neurons and is the source of myelin; a single Schwann cell supplies the myelin sheath between two nodes of Ranvier.

Medical dictionary. 2011.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Schwann cell — Schwann′ cell n. hic (lab cbl) a cell of the peripheral nervous system that wraps around a nerve fiber, jelly roll fashion, forming the myelin sheath • Etymology: 1930–35; after T. Schwann, who first described it …   From formal English to slang

  • Schwann cell — [shwän] n. any of the cells covering the myelin sheath that surrounds and insulates an axon of a nerve cell: see also NODE OF RANVIER …   English World dictionary

  • Schwann cell — Structure of a typical neuron Schwann cells wrapped around an axon Dendrite …   Wikipedia

  • Schwann cell — noun any cell that covers the nerve fibers in the peripheral nervous system and forms the myelin sheath • Hypernyms: ↑somatic cell, ↑vegetative cell * * * ˈshw]än , ˈshf], ˈshv] noun Usage: usually capitalized S Etymology: after Theodor Schwann… …   Useful english dictionary

  • Schwann cell — noun Etymology: Theodor Schwann died 1882 German naturalist Date: circa 1909 the myelin secreting cell surrounding a myelinated nerve fiber between two nodes of Ranvier …   New Collegiate Dictionary

  • Schwann cell — Biol. a cell of the peripheral nervous system that wraps around a nerve fiber, jelly roll fashion, forming the myelin sheath. [1930 35; after T. SCHWANN, who first described it] * * * …   Universalium

  • Schwann cell — (ARTHROPODA: Insecta) An elongate cell into which motor axons sink and become suspended by a suspensory fold; lemnoblast; neurilemma cell …   Dictionary of invertebrate zoology

  • Schwann cell — A specialized glial cell that wraps around vertebrate axons providing extremely good electrical insulation. Separated by nodes of Ranvier about once every millimetre, at which the axon surface is exposed to the environment. See saltatory… …   Dictionary of molecular biology

  • Schwann cell — A type of glial cell of the peripheral nervous system that helps separate and insulate nerve cells …   English dictionary of cancer terms

  • Schwann cell membrane (sheath) nucleus substance — (shvahn) [Theodor Schwann, German anatomist and physiologist, 1810–1882] see under cell and nucleus, and see neurilemma …   Medical dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”