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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...

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...

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...

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...

attention deficit hyperactivity disorder

(Encyclopedia)attention deficit hyperactivity disorder (ADHD), formerly called hyperkinesis or minimal brain dysfunction, a chronic, neurologically based syndrome characterized by any or all of three types of behav...

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...

Dickey, Eric Jerome

(Encyclopedia)Dickey, Eric Jerome, 1961- 2021, African-American author, b. Memphis, TN, Memphis State Univ. (BS, 1983). Dickey studied engineering and, after completi...

Gibbs, Josiah Willard

(Encyclopedia)Gibbs, Josiah Willard, 1839–1903, American mathematical physicist, b. New Haven, Conn., grad. Yale, 1858. He studied abroad and was professor of mathematical physics at Yale from 1871. His great con...