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multiple sclerosis

(Encyclopedia)multiple sclerosis (MS), chronic, slowly progressive autoimmune disease in which the body's immune system attacks the protective myelin sheaths that surround the nerve cells of the brain and spinal co...

crossing over

(Encyclopedia)crossing over, process in genetics by which the two chromosomes of a homologous pair exchange equal segments with each other. Crossing over occurs in the first division of meiosis. At that stage each ...

cytosine

(Encyclopedia)cytosine sīˈtōsēnˌ [key], organic base of the pyrimidine family. It was isolated from the nucleic acid of calf thymus tissue in 1894. A suggested structure for cytosine, published in 1903, was co...

glycine

(Encyclopedia)CE5 glycine glīˈsēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Glycine is the only one of these amino acids that is not optically active, i.e., it does...

eukaryote

(Encyclopedia)eukaryote yo͞okârˈē-ōtˌ [key], a cell or organism composed of cells that have a membrane-bound nucleus and organelles (mitochondria, chloroplasts; see cell, in biology) and genetic material orga...

Khoikhoi

(Encyclopedia)Khoikhoi koiˈkoiˌ [key], people numbering about 55,000 mainly in Namibia and in W South Africa. The Khoikhoi have been called Hottentots by whites in South Africa. In language and in physical type t...

Glasgow, city, Scotland

(Encyclopedia)Glasgow glăsˈgō, –kō, glăzˈgō [key], city and council area, S central Scotla...

Atanasoff, John Vincent

(Encyclopedia)Atanasoff, John Vincent, 1903–1995, inventor of the digital computer, b. Hamilton, N.Y., grad. Univ. of Florida (B.S., 1925), Iowa State College (M.S., 1926), Univ. of Wisconsin (Ph.D., 1930). While...

McPherson, James Birdseye

(Encyclopedia)McPherson, James Birdseye, 1828–64, Union general in the American Civil War, b. Sandusky co., Ohio. After teaching (1853–54) at West Point, he worked on various engineering projects. In the Civil ...