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Monod, Jacques

(Encyclopedia)Monod, Jacques zhäk mônōˈ [key], 1910–76, French biologist, educated at the Univ. of Paris (D.Sc., 1941). He was a leader of the French resistance in World War II. He shared the 1965 Nobel Prize...

Opalinida

(Encyclopedia)Opalinida ōˌpəlĭnˈĭdə [key], phylum of unicellular heterotrophic organisms of the kingdom Protista. The opalinids are all intestinal parasites of small vertebrates, such as frogs, toads, and fi...

Krebs, Edwin Gerhard

(Encyclopedia)Krebs, Edwin Gerhard, 1918–2009, American biochemist, b. Lansing, Iowa. He and fellow Univ. of Washington professor Edmond Fischer discovered a biological regulatory mechanism, reversible protein ph...

Buchner, Eduard

(Encyclopedia)Buchner, Eduard āˈdo͞oärt bo͞okhˈnər [key], 1860–1917, German chemist. He taught at Berlin, Breslau, and, from 1911, at Würzburg. He discovered (1896) that alcoholic fermentation of sugars i...

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...

membrane

(Encyclopedia)membrane, structure composed mostly of lipid and protein that forms the external boundary of cells and of major structures within cells. Membrane organization is based on a sheet two molecules thick�...

parathyroid hormone

(Encyclopedia)parathyroid hormone or parathormone, a hormone secreted by the parathyroid glands that regulates the metabolism of calcium and phosphate in the body. It has been purified extensively and appears to be...

blood test

(Encyclopedia)blood test, examination of blood routinely or as an aid in diagnosing a suspected disease. Tests may be performed on whole blood or on the plasma portion only. Blood typing identifies the proteins at ...

spore

(Encyclopedia)spore, term applied both to a resistant or resting stage occurring among various unicellular organisms (especially bacteria) and to an asexual reproductive cell produced by many unicellular plants and...

HIV

(Encyclopedia)HIV, human immunodeficiency virus, either of two closely related retroviruses that invade T-helper lymphocytes and are responsible for AIDS. There are two types of HIV: HIV-1 and HIV-2. HIV-1 is respo...