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space law

(Encyclopedia)space law, agreements governing the exploration and use of outer space, developed since the first launching (1957) by humans of a satellite into space. Space law, an aspect of international law, has g...

Porifera

(Encyclopedia)CE5 A. Canal systems of the three morphological types of sponges B. Internal anatomy of an asconoid sponge, representative of the phylum Porifera Porifera pōrĭfˈərə [key] [Lat.,=pore bearer],...

echo sounder

(Encyclopedia)echo sounder, an older instrumentation system for indirectly determining ocean floor depth. Echo sounding is based on the principle that water is an excellent medium for the transmission of sound wave...

membrane

(Encyclopedia)membrane, structure composed mostly of lipid and protein that forms the external boundary of cells and of major structures within cells. Membrane organization is based on a sheet two molecules thick�...

artery

(Encyclopedia)artery, blood vessel that conveys blood away from the heart. Except for the pulmonary artery, which carries deoxygenated blood from the heart to the lungs, arteries carry oxygenated blood from the hea...

paper

(Encyclopedia)paper, thin, flat sheet or tissue made usually from plant fiber but also from rags and other fibrous materials. It is used principally for printing and writing on but has many other applications. The ...

cortisol

(Encyclopedia)cortisol kôrˈtĭsôlˌ [key] or hydrocortisone, steroid hormone that in humans is the major circulating hormone of the cortex, or outer layer, of the adrenal gland. Like cortisone, cortisol is class...

acne

(Encyclopedia)acne, common inflammatory disease of the hair follicles and sebaceous glands characterized by blackheads, whiteheads, pustules, nodules and, in the more severe forms, by cysts and scarring. The lesion...

Tudor style

(Encyclopedia)Tudor style, descriptive of the English architecture and decoration of the first half of the 16th cent., prevailing during the reigns (1485–1558) of Henry VII, Henry VIII, Edward VI, and Mary I. It ...

transpiration

(Encyclopedia)transpiration, in botany, the loss of water by evaporation in terrestrial plants. Some evaporation occurs directly through the exposed walls of surface cells, but the greatest amount takes place throu...