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Yonath, Ada E.

(Encyclopedia)Yonath, Ada E., 1939–, Israeli crystallographer, Ph.D. Weizmann Institute of Science, Rehovat, Israel, 1968. Yonath has been a researcher and professor at the Weizmann Institute since 1970. She was ...

cheese

(Encyclopedia)cheese, food known from ancient times and consisting of the curd of milk separated from the whey. The numerous cheeses (often named for their place of origin) depend for their distinctive qualities ...

gene

(Encyclopedia)gene, the structural unit of inheritance in living organisms. A gene is, in essence, a segment of DNA that has a particular purpose, i.e., that codes for (contains the chemical information necessary f...

silver

(Encyclopedia)silver, metallic chemical element; symbol Ag [Lat. argentum]; at. no. 47; at. wt. 107.8682; m.p. 961.93℃; b.p. 2,212℃; sp. gr. 10.5 at 20℃; valence +1 or +2. Pure silver is nearly white, lustrou...

penicillin

(Encyclopedia)penicillin, any of a group of chemically similar substances obtained from molds of the genus Penicillium that were the first antibiotic agents to be used successfully in the treatment of bacterial inf...

melanin

(Encyclopedia)melanin mĕlˈənĭn [key], water-insoluble polymer of various compounds derived from the amino acid tyrosine. It is one of two pigments found in human skin and hair and adds brown to skin color; the ...

mountain laurel

(Encyclopedia)mountain laurel, evergreen shrub (Kalmia latifolia) of the family Ericaceae (heath family), closely related to the rhododendron and native to E North America. The state flower of Connecticut and Penns...

mango

(Encyclopedia)mango măngˈgō [key], evergreen tree of the Anacardiaceae (sumac family), native to tropical E Asia and now grown in both hemispheres. The chief species, Mangifera indica, is believed to have been c...

Rothamsted

(Encyclopedia)Rothamsted rŏthˈəmstĭd [key], world's oldest and England's most important agricultural experiment station, now the main center of the Institute of Arable Crops Research (IACR). It was founded in 1...

thallium

(Encyclopedia)thallium thălˈēəm [key], metallic chemical element; symbol Tl; at. no. 81; interval in which at. wt. ranges 204.382–204.385; m.p. 303.5℃; b.p. about 1,457℃; sp. gr. 11.85 at 20℃; valence +...