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histamine

(Encyclopedia)histamine hĭsˈtəmēnˌ [key], organic compound derived in the body from the amino acid histidine by the removal of a carboxyl group (COOH). Although found in many plant and animal tissues, histamin...

histone

(Encyclopedia)histone hĭsˈtōn [key], any of a class of protein molecules found in the chromosomes of eukaryotic cells. They complex with the DNA (see nucleic acid) and pack the DNA into tight masses of chromatin...

Duane, William, American journalist

(Encyclopedia)Duane, William, 1760–1835, American journalist, b. near Lake Champlain, N.Y., of Irish parentage. He learned the printer's trade in Ireland and in 1787 went to Calcutta (now Kolkata), where he edite...

sodium bicarbonate

(Encyclopedia)sodium bicarbonate or sodium hydrogen carbonate, chemical compound, NaHCO3, a white crystalline or granular powder, commonly known as bicarbonate of soda or baking soda. It is soluble in water and ver...

wintergreen

(Encyclopedia)wintergreen or checkerberry, low evergreen plant (Gaultheria procumbens) of the family Ericaceae (heath family), native to sandy and acid woods (usually of evergreens) of E North America and frequentl...

blueberry

(Encyclopedia)blueberry, plant of the large genus Vaccinium, widely distributed shrubs (occasionally small trees) of the family Ericaceae (heath family), usually found on acid soil. They are often confused with the...

charcoal

(Encyclopedia)charcoal, substance obtained by partial burning or carbonization (destructive distillation) of organic material. It is largely pure carbon. The entry of air during the carbonization process is control...

ozone layer

(Encyclopedia)ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone, located at altitudes of 12–30 mi (19–48 km) above the earth's surface. Ozone in the ozone...

iodine

(Encyclopedia)iodine īˈədīn, –dĭn [key] [Gr.,=violet], nonmetallic chemical element; symbol I; at. no. 53; at. wt. 126.90447; m.p. 113.5℃; b.p. 184.35℃; sp. gr. 4.93 at 20℃; valence −1, +1, +3, +5, o...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...