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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...

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...

genetic engineering

(Encyclopedia)CE5 Genetic engineering: Gene-splicing techniques genetic engineering, the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biologica...

water supply

(Encyclopedia)water supply, process or activity by which water is provided for some use, e.g., to a home, factory, or business. The term may also refer to the supply of water provided in this way. In the United Sta...

alfalfa

(Encyclopedia)alfalfa lo͞osûnˈ [key], perennial leguminous plant (Medicago sativa) of the family Leguminosae (pulse family), the most important pasture and hay plant in North America, also grown extensively in A...

cholera

(Encyclopedia)cholera kŏlˈərə [key] or Asiatic cholera, acute infectious disease caused by strains of the bacterium Vibrio cholerae that have been infected by bacteriophages. The bacteria, which are found in fe...

endocarditis

(Encyclopedia)endocarditis ĕnˌdōkärdīˈtĭs [key], bacterial or fungal infection of the endocardium (inner lining of the heart) that can be either acute or subacute. In the acute form the symptoms (fever, mala...

fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...