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Rodbell, Martin

(Encyclopedia)Rodbell, Martin, 1925–1998, American biochemist, b. Baltimore, Ph.D. Univ. of Washington, 1954. He was a researcher (1956–1985) at the National Heart Institute in Bethesda, Md., before becoming sc...

monoclonal antibody

(Encyclopedia)monoclonal antibody, an antibody that is mass produced in the laboratory from a single clone and that recognizes only one antigen. Monoclonal antibodies are typically made by fusing a normally short-l...

battery, electric

(Encyclopedia)CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...

protozoan

(Encyclopedia)protozoan prōˌtəzōˈən [key], informal term for the unicellular heterotrophs of the kingdom Protista. Protozoans comprise a large, diverse assortment of microscopic or near-microscopic organisms ...

Gram's stain

(Encyclopedia)Gram's stain, laboratory staining technique that distinguishes between two groups of bacteria by the identification of differences in the structure of their cell walls. The Gram stain, named after its...

carbon cycle

(Encyclopedia)CE5 Carbon cycle carbon cycle, in biology, the exchange of carbon between living organisms and the nonliving environment. Inorganic carbon dioxide in the atmosphere is converted by plants into sim...

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...

diatom

(Encyclopedia)diatom dīˈətŏmˌ, –tōmˌ [key], unicellular organism of the kingdom Protista, characterized by a silica shell of often intricate and beautiful sculpturing. Most diatoms exist singly, although s...

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�...

Haldane, John Burdon Sanderson

(Encyclopedia)Haldane, John Burdon Sanderson hôlˈdān, –dən [key], 1892–1964, British geneticist, biologist, and popularizer of science; son of John Scott Haldane. He studied at Oxford until his studies were...