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glycoprotein

(Encyclopedia)glycoprotein glīˌkōprōˈtēn [key], organic compound composed of both a protein and a carbohydrate joined together in covalent chemical linkage. These structures occur in many life forms; they are...

Johnson, Sir William

(Encyclopedia)Johnson, Sir William, 1715–74, British colonial leader in America, b. Co. Meath, Ireland. He settled (1738) in the Mohawk valley, became a merchant, and gained great power among the Mohawk and other...

molecular biology

(Encyclopedia)molecular biology, scientific study of the molecular basis of life processes, including cellular respiration, excretion, and reproduction. The term molecular biology was coined in 1938 by Warren Weave...

neutron

(Encyclopedia)neutron, uncharged elementary particle of slightly greater mass than the proton. It was discovered by James Chadwick in 1932. The stable isotopes of all elements except hydrogen and helium contain a n...

Cárdenas, Lázaro

(Encyclopedia)Cárdenas, Lázaro ko͞o-outāˈmôk, sōlôrˈsänō [key], 1934–, seen since the 1980s as his father's political heir, held posts within the ruling Institutional Revolutionary party (PRI) before 1...

technetium

(Encyclopedia)technetium tĕknēˈshēəm [key] [Gr. technetos=artificial], artificially produced radioactive chemical element; symbol Tc; at. no. 43; mass no. of most stable isotope 98; m.p. 2,200℃; b.p. 4,877�...

radon

(Encyclopedia)radon rāˈdŏn [key], gaseous radioactive chemical element; symbol Rn; at. no. 86; mass no. of most stable isotope 222; m.p. about −71℃; b.p. −61.8℃; density 9.73 grams per liter at STP; vale...

seaborgium

(Encyclopedia)seaborgium sēbôrˈgēəm [key], artificially produced radioactive chemical element; symbol Sg; at. no. 106; mass number of most stable isotope 271; m.p., b.p., sp. gr., and valence unknown. Situated...

sponge

(Encyclopedia)sponge, common name for members of the aquatic animal phylum Porifera, and for the dried, processed skeletons of certain species used to hold water. Over 4,500 living species are known; they are found...

cremation

(Encyclopedia)cremation, disposal of a corpse by fire. It is an ancient and widespread practice, second only to burial. It has been found among the tribes of the Pacific Northwest, among Northern Athapascan bands i...