Schwann cell

neu·ri·lem·ma   (nŏŏr'ə-lěm'ə, nyŏŏr'-)    n.   Any of the cells having a membrane that composes a sheath around the axons of peripheral nerves. Also called Schwann cell. The sheath formed by such a cell. [Alteration (influenced by Greek lemma, husk) of French névrilème : névr-, nerve (from Greek neuro-, neuro-) + Greek eilēma, veil (from eilein, to wind, turn; see wel-2 in Indo-European roots).] neu'ri·lem'mal adj.

Main Entry: Schwann cell
Pronunciation: 'shwän-
Function: noun
: a cell that forms spiral layers around a myelinated nerve fiber between two nodes ofRanvier 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: hedefined 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 preparedfrom animal tissue pepsin. Schwann is also regarded as a founder of the germ theory of putrefaction and fermentation. In 1837 he published proof that putrefaction is produced by living bodies.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 hepublished 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 acomplete organism.

Schwann cell (shwän, shvän)
n.
Any of the cells that cover the nerve fibers in the peripheral nervous system and form the myelin sheath. Also called neurilemma cell.