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(Encyclopedia)marmalade [Port.,=quince preparation], thick preserve of fruit pulp, originally made from quinces (marmelos) and known in England from the 15th cent.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

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...

fluoride

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

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...

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...

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....

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...

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...

antiseptic

(Encyclopedia)antiseptic, agent that kills or inhibits the growth of microorganisms on the external surfaces of the body. Antiseptics should generally be distinguished from drugs such as antibiotics that destroy mi...