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classification

(Encyclopedia)CE5 classification, in biology, the systematic categorization of organisms into a coherent scheme. The original purpose of biological classification, or systematics, was to organize the vast number...

reproduction

(Encyclopedia)CE5 Examples of asexual reproduction reproduction, capacity of all living systems to give rise to new systems similar to themselves. The term reproduction may refer to this power of self-duplicati...

folk medicine

(Encyclopedia)folk medicine, methods of curing by means of healing objects, herbs, or animal parts; ceremony; conjuring, magic, or witchcraft; and other means apart from the formalized practice of medical science. ...

dust, atmospheric

(Encyclopedia)dust, atmospheric, minute particles slowly settling or suspended by slight currents and existing in varying amounts in all air. There is least dust at high levels over the ocean and most at low levels...

plant

(Encyclopedia)plant, any organism of the plant kingdom, as opposed to one of the animal kingdom or of the kingdoms Fungi, Protista, or Monera in the five-kingdom system of classification. (A more recent system, sug...

truffle

(Encyclopedia)truffle trŭfˈəl [key] [Fr.], subterranean edible fungus that forms a mutually beneficial (symbiotic) relationship with the roots of certain trees and plants. The part of the fungus used as food is ...

mercury poisoning

(Encyclopedia)mercury poisoning, tissue damage resulting from exposure to more than trace amounts of the element mercury or its compounds. Elemental mercury (the silver liquid familiar from thermometers) is the mos...

aphid

(Encyclopedia)aphid or plant louse, tiny, usually green, soft-bodied, pear-shaped insect injurious to vegetation. It is also called greenfly and blight. Aphids are mostly under 1⁄4 in. (6 mm) long. Some are wingl...

penicillin

(Encyclopedia)penicillin, any of a group of chemically similar substances obtained from molds of the genus Penicillium that were the first antibiotic agents to be used successfully in the treatment of bacterial inf...

pesticide

(Encyclopedia)pesticide, biological, physical, or chemical agent used to kill plants or animals that are harmful to people; in practice, the term pesticide is often applied only to chemical agents. Various pesticid...