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antibody

(Encyclopedia)antibody, protein produced by the immune system (see immunity) in response to the presence in the body of antigens: foreign proteins or polysaccharides such as bacteria, bacterial toxins, viruses, or ...

gonorrhea

(Encyclopedia)gonorrhea gŏnərēˈə [key], common infectious disease caused by a bacterium (Neisseria gonorrhoeae), involving chiefly the mucous membranes of the genitourinary tract. It may occasionally spread to...

food additives

(Encyclopedia)food additives, substances added to foods by manufacturers to prevent spoilage or to enhance appearance, taste, texture, or nutritive value. By quantity, the most common food additives are flavorings,...

appendix

(Encyclopedia)appendix, small, worm-shaped blind tube, about 3 in. (7.6 cm) long and 1⁄4 in. to 1 in. (.64–2.54 cm) thick, projecting from the cecum (part of the large intestine) on the right side of the lower ...

luminescence

(Encyclopedia)luminescence, general term applied to all forms of cool light, i.e., light emitted by sources other than a hot, incandescent body, such as a blackbody radiator. Luminescence is caused by the movement ...

blood test

(Encyclopedia)blood test, examination of blood routinely or as an aid in diagnosing a suspected disease. Tests may be performed on whole blood or on the plasma portion only. Blood typing identifies the proteins at ...

spore

(Encyclopedia)spore, term applied both to a resistant or resting stage occurring among various unicellular organisms (especially bacteria) and to an asexual reproductive cell produced by many unicellular plants and...

Rotifera

(Encyclopedia)Rotifera, phylum of predominantly free-living, microscopic, aquatic or semiterrestrial pseudocoelomates. Each rotifer has a head bearing a crown of cilia, the corona, at the anterior end; most rotifer...

relapsing fever

(Encyclopedia)relapsing fever, infectious disease caused by a spirochete bacteria of the genus Borrelia and characterized by a high fever that breaks and then recurs a one to two weeks later. Relapsing fever may be...

pitcher plant

(Encyclopedia)pitcher plant, any of several insectivorous plants with leaves adapted for trapping insects. Each leaf forms a “pitcher,” a somewhat trumpet-shaped enclosure, usually containing a liquid. An insec...