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chloroplast

(Encyclopedia)chloroplast klōrˈəplăstˌ, klôrˈ– [key], a complex, discrete green structure, or organelle, contained in the cytoplasm of plant cells. Chloroplasts are reponsible for the green color of almost...

Ajivika

(Encyclopedia)Ajivika äjēˈvĭkə [key], religious sect of medieval India, once of major importance. The Ajivikas were an ascetic, atheistic, anti-Brahmanical community whose pessimistic doctrines are related to ...

executive privilege

(Encyclopedia)executive privilege, exemption of the executive branch of government, or its officers, from having to give evidence, specifically, in U.S. law, the exemption of the president from disclosing informati...

Fire, Andrew Zachary

(Encyclopedia)Fire, Andrew Zachary, 1959–, American geneticist, b. Palo Alto, Calif., Ph.D. Massachusetts Institute of Technology, 1983. After a long association with the Carnegie Institution of Washington (1986�...

firing

(Encyclopedia)firing, process of treating clay or other plastic ceramic materials with heat to produce a hard, durable but brittle material such as pottery. Primitive potters baked their clay in an open fire, but f...

Grand Forks

(Encyclopedia)Grand Forks, city (2020 pop. 59,166), seat of Grand Forks co., E N.Dak., at the confluence of the Red and the Red Lake rivers; inc. 1881. In a spring wh...

pressure-treated wood

(Encyclopedia)pressure-treated wood, wood that has had a liquid preservative forced into it in order to protect against deterioration due to rot or insect attack. The most commonly used preservatives are chromated ...

Ostwald, Wilhelm

(Encyclopedia)Ostwald, Wilhelm vĭlˈhĕlm ôstˈvält [key], 1853–1932, German physical chemist and natural philosopher, b. Riga, Latvia. He was professor of chemistry and director of the chemical laboratory (18...

galvanizing

(Encyclopedia)galvanizing, process of coating a metal, usually iron or steel, with a protective covering of zinc. Galvanized iron is prepared either by dipping iron, from which rust has been removed by the action o...

Hershko, Avram

(Encyclopedia)Hershko, Avram, 1937–, Israeli biochemist, M.D. Hebrew Univ.–Hadassah Medical School, Jerusalem, 1965, Ph.D. 1969. Hershko has been a professor at the Rappaport Faculty of Medicine at the Technion...