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Krebs cycle

(Encyclopedia)Krebs cycle, series of chemical reactions carried out in the living cell; in most higher animals, including humans, it is essential for the oxidative metabolism of glucose and other simple sugars. The...

Szostak, Jack William

(Encyclopedia)Szostak, Jack William, 1952–, American molecular biologist, b. London, England, Ph.D. Cornell, 1977. Szostak has been a professor at Harvard Medical School and a researcher at Massachusetts General ...

hydrogen chloride

(Encyclopedia)hydrogen chloride, chemical compound, HCl, a colorless, poisonous gas with an unpleasant, acrid odor. It is very soluble in water and readily soluble in alcohol and ether. It fumes in moist air. It is...

Modrich, Paul Lawrence

(Encyclopedia)Modrich, Paul Lawrence, 1946–, American biochemist and molecular geneticist, b. Raton, N.M., Ph.D. Stanford Univ., 1973. Modrich joined the faculty at the Duke Univ. School of Medicine in 1976, and ...

neutralization

(Encyclopedia)neutralization, chemical reaction, according to the Arrhenius theory of acids and bases, in which a water solution of acid is mixed with a water solution of base to form a salt and water; this reactio...

tannin

(Encyclopedia)tannin, tannic acid, or gallotannic acid, astringent vegetable product found in a wide variety of plants. Sources include the bark of oak, hemlock, chestnut, and mangrove; the leaves of certain sumac...

McClintock, Barbara

(Encyclopedia)McClintock, Barbara, 1902–92, American geneticist. She discovered that certain genetic material, “transposable elements” or “jumping genes” (now called transposons), shifted its location in ...

sunburn

(Encyclopedia)sunburn, inflammation of the skin caused by actinic rays from the sun or artificial sources. Moderate exposure to ultraviolet radiation is followed by a red blush, but severe exposure may result in bl...

macromolecule

(Encyclopedia)macromolecule, term that may refer either to a crystal such as a diamond, in which the atoms are identical and held by covalent bonds (see chemical bond) of equal strength, or to one of the units that...

acids and bases

(Encyclopedia)acids and bases, two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Another theory that provides a very broad ...