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tilapia

(Encyclopedia)tilapia təläˈpēə [key] or St. Peter's fish, a spiny-finned freshwater fish of the family Cichlidae, native chiefly to Africa and the Middle East. Fish of the genera Oreochromis, Sarotherodon, and...

rickets

(Encyclopedia)rickets or rachitis rəkīˈtĭs [key], bone disease caused by a deficiency of vitamin D or calcium. Essential in regulating calcium and phosphorus absorption by the body, vitamin D can be formed in t...

Dickinson, Peter

(Encyclopedia)Dickinson, Peter (Peter Malcolm de Brissac Dickinson), 1927–2015, b. Livingstone, Northern Rhodesia (now Zambia). The son of a civil servant, he returned to England (1935) with his family and attend...

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...

Allison, James Patrick

(Encyclopedia)Allison, James Patrick, 1948–, American immunologist, b. Alice, Tex., Ph.D. Univ. of Texas, Austin, 1973. Allison was a researcher at the Univ. of Texas System Cancer Center in Houston from 1977 to ...

physical fitness

(Encyclopedia)physical fitness, combined good health and physical development. The object of any program of physical fitness is to maximize an individual's health, strength, endurance, and skill relative to age, se...

tick

(Encyclopedia)tick, small, parasitic arachnid of the order Ixodida, closely related to the mites. Ticks, which are larger than the often microscopic mites, are all parasitic in at least one developmental stage; mos...

sea star

(Encyclopedia)sea star, also called starfish, echinoderm of the class Asteroidae, common in tide pools. Sea stars vary in size from under 1⁄2 in. (1.3 cm) to over 3 ft (90 cm) in diameter. They are commonly dull ...

ventilation

(Encyclopedia)ventilation, process of supplying fresh air to an enclosed space and removing from it air contaminated by odors, gases, or smoke. Proper ventilation requires also that there be a movement or circulati...

potato

(Encyclopedia)potato or white potato, common name for a perennial plant (Solanum tuberosum) of the family Solanaceae (nightshade family) and for its swollen underground stem, a tuber, which is one of the most widel...