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complex variable analysis

(Encyclopedia)complex variable analysis, branch of mathematics that deals with the calculus of functions of a complex variable, i.e., a variable of the form z=x+iy, where x and y are real and i=−1 (see number). A...

computer program

(Encyclopedia)computer program, a series of instructions that a computer can interpret and execute; programs are also called software to distinguish them from hardware, the physical equipment used in data processin...

chiton

(Encyclopedia)CE5 A. Dorsal view of a chiton, representative mollusk of the class Amphineura B. Internal anatomy of a chiton chiton kīˈtən [key], common name for rock-clinging marine mollusks of the class Po...

gear

(Encyclopedia)CE5 Types of gears gear, toothed wheel, cylinder, or cone that transmits motion from one part of a machine to another; it is one of the oldest means of transmitting motion. When the teeth of two g...

German Confederation

(Encyclopedia)CE5 German Confederation (1815) German Confederation, 1815–66, union of German states provided for at the Congress of Vienna to replace the old Holy Roman Empire, which had been destroyed during...

gills, in biology

(Encyclopedia)CE5 Gills of a fish: Side view (A) and ventral view (B) gills, external respiratory organs of most aquatic animals. In fishes the gills are located in gill chambers at the rear of the mouth (phary...

tyrosine

(Encyclopedia)CE5 tyrosine tīˈrəsēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is not essential to the huma...

food pyramid

(Encyclopedia)CE5 The U.S. Department of Agriculture used (1992–2005) this pyramid to show the basis of a healthy diet, dividing foods into five nutritional groups and recommending the number of daily average ...

foot, in anatomy

(Encyclopedia)CE5 Foot foot, in anatomy, terminal part of the land vertebrate leg. The term is also applied to any invertebrate appendage used either for locomotion or attachment, e.g., the legs of insects and ...

histidine

(Encyclopedia)CE5 histidine hĭsˈtĭdēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. Histidine is the direct pr...