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chlorine

(Encyclopedia)chlorine klōrˈēn, klôrˈ– [key] [Gr.,=green], gaseous chemical element; symbol Cl; at. no. 17; interval in which at. wt. ranges 35.446–35.457; m.p. −100.98℃; b.p. −34.6℃; density 3.2 g...

marmalade

(Encyclopedia)marmalade [Port.,=quince preparation], thick preserve of fruit pulp, originally made from quinces (marmelos) and known in England from the 15th cent. Marmalade has a jellylike consistency and a slight...

fluoride

(Encyclopedia)fluoride, a salt of hydrofluoric acid; see hydrogen fluoride. See also fluoridation; fluorine. ...

operon

(Encyclopedia)operon, in genetics, site on a bacterial chromosome containing genes that control protein synthesis (structural genes) together with a gene that determines whether the structural genes are active or n...

mucopolysaccharide

(Encyclopedia)mucopolysaccharide myo͞oˌkəpŏlēsăkˈərīd [key], class of polysaccharide molecules, also known as glycosaminoglycans, composed of amino-sugars chemically linked into repeating units that give a...

Goldberger, Joseph

(Encyclopedia)Goldberger, Joseph, 1874–1929, American medical research worker, b. Austria-Hungary, grad. Bellevue Hospital Medical College, 1895. He came to the United States at the age of six. He joined the U.S....

Gerhardt, Charles Frédéric

(Encyclopedia)Gerhardt, Charles Frédéric shärl frādārēkˈ zhārärˈ [key], 1816–56, French chemist, b. Strasbourg. He revived the theory of acid radicals, which he called the theory of residues, and did va...

bone meal

(Encyclopedia)bone meal, finely ground bone used as a fertilizer for its content of phosphate and nitrogen (about 23%–30% available phosphate and 2%–4% nitrogen); it is an expensive form of phosphoric acid when...

jelly and jam

(Encyclopedia)jelly and jam, gelatinous, sweet food prepared by preserving fresh fruits. Since most fresh fruits contain about 80% water and from 10% to 15% sugar, they are subject to fermentation. They may be pres...

glucagon

(Encyclopedia)glucagon glo͞oˈkəgŏn [key], hormone secreted by the α cells of the islets of Langerhans, specific groups of cells in the pancreas. It tends to counteract the action of insulin, i.e., it raises th...