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protozoan

(Encyclopedia)protozoan prōˌtəzōˈən [key], informal term for the unicellular heterotrophs of the kingdom Protista. Protozoans comprise a large, diverse assortment of microscopic or near-microscopic organisms ...

medicine

(Encyclopedia)medicine, the science and art of treating and preventing disease. Modern medicine, characterized by growing specialization and a complex diagnostic and therapeutic technology, faces problems in the...

cigar and cigarette

(Encyclopedia)cigar and cigarette, tubular rolls of tobacco designed for smoking. Cigars consist of filler leaves held together by binder leaves and covered with a wrapper leaf, which is rolled spirally around the ...

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...

schizophrenia

(Encyclopedia)schizophrenia skĭtˌsəfrēˈnēə [key], group of severe mental disorders characterized by reality distortions resulting in unusual thought patterns and behaviors. Because there is often little or n...

plague

(Encyclopedia)plague, any contagious, malignant, epidemic disease, in particular the bubonic plague and the black plague (or Black Death), both forms of the same infection. These acute febrile diseases are caused b...

vineyard

(Encyclopedia)vineyard, land on which cultivation of the grape—known as viticulture—takes place. As many as 40 varieties of grape, Vitis vinifera, are known. The few that grow wild are generally not used; all d...

ameba

(Encyclopedia)ameba or amoeba both: əmēˈbə [key], common name for certain one-celled organisms belonging to the phylum Sarcodina of the kingdom Protista. Amebas were previously classified as members of the anim...

mouse

(Encyclopedia)mouse, name applied to numerous species of small rodents, often having soft gray or brown fur, long hairless tails, and large ears. The chief distinction between these animals and the variety of roden...

mental retardation

(Encyclopedia)mental retardation, below average level of intellectual functioning, usually defined by an IQ of below 70 to 75, combined with limitations in the skills necessary for daily living. Daily living skills...