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denaturation

(Encyclopedia)denaturation, term used to describe the loss of native, higher-order structure of protein molecules in solution. Most globular proteins exhibit complicated three-dimensional folding described as secon...

nucleic acid

(Encyclopedia)CE5 Replication of strands of DNA CE5 nucleic acid, any of a group of organic substances found in the chromosomes of living cells and viruses that play a central role in the storage and replica...

trapezoid

(Encyclopedia)trapezoid, closed plane figure bounded by four line segments, or sides, two of which are parallel and two of which are nonparallel. The parallel sides of a trapezoid are called bases and the nonparall...

iridium

(Encyclopedia)iridium ĭrĭdˈēəm [key], metallic chemical element; symbol Ir; at. no. 77; at. wt. 192.217; m.p. about 2,410℃; b.p. about 4,130℃; sp. gr. 22.55 at 20℃; valence +3 or +4. Iridium is a very ha...

peptide

(Encyclopedia)peptide, organic compound composed of amino acids linked together chemically by peptide bonds. The peptide bond always involves a single covalent link between the α-carboxyl (oxygen-bearing carbon) o...

fatty acid

(Encyclopedia)fatty acid, any of the organic carboxylic acids present in fats and oils as esters of glycerol. Molecular weights of fatty acids vary over a wide range. The carbon skeleton of any fatty acid is unbran...

W and Z particles

(Encyclopedia)W and Z particles, elementary particles that mediate, or carry, the fundamental force associated with weak interactions. The discovery of the W and Z particles at CERN near Geneva, Switzerland, in the...

Wieland, Heinrich

(Encyclopedia)Wieland, Heinrich, 1877–1957, German chemist, Ph.D. Univ. of Munich, 1901. Wieland was a professor at the Technical Univ. of Munich from 1913 to 1921, the Univ. of Freiburg from 1921 to 1925, and th...

oxide

(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...

South Shetland Islands

(Encyclopedia)South Shetland Islands, barren, snow-covered archipelago off N Antarctic Peninsula, W Antarctica; Livingston and King George islands are the largest. The South Shetlands were bases for sealers in the ...