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placenta

(Encyclopedia)placenta pləsĕnˈtə [key] or afterbirth, organ that develops in the uterus during pregnancy. It is a unique characteristic of the higher (or placental) mammals. In humans it is a thick mass, about ...

silage

(Encyclopedia)silage ĕnˈsəlĭj [key], succulent, moist feed made by storing a green crop in a silo. The crop most used for silage is corn; others are sorghum, sunflowers, legumes, and grass. In a sealed silo, ty...

Rhea, in astronomy

(Encyclopedia)Rhea, in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn V (or S5), Rhea is 950 mi (1530 km) in diameter, orbits Saturn at a mean distance of 327,487 mi (527,...

glycolysis

(Encyclopedia)glycolysis glīkŏlˈĭsĭs [key], term given to the metabolic pathway utilized by most microorganisms (yeast and bacteria) and by all “higher” animals (including humans) for the degradation of gl...

electronegativity

(Encyclopedia)electronegativity ĭlĕkˌtrōnĕgətĭvˈətē [key], in chemistry, tendency for an atom to attract a pair of electrons that it shares with another atom (see chemical bond). For example, the molecule...

nitrous oxide

(Encyclopedia)nitrous oxide or nitrogen (I) oxide, chemical compound, N2O, a colorless gas with a sweetish taste and odor. Its density is 1.977 grams per liter at STP. It is soluble in water, alcohol, ether, and ot...

polycythemia

(Encyclopedia)polycythemia pŏlˌēsīthēˈmēə [key], condition characterized by an increase in the production of red blood cells, or erythrocytes, in the blood. Primary polycythemia, also called erythremia, or ...

synthetic textile fibers

(Encyclopedia)synthetic textile fibers have revolutionized the textile industry. Such artificial fibers are usually long-chain polymers, produced industrially by the condensation of many small units. Orlon is the t...

thrombosis

(Encyclopedia)thrombosis thrŏmbōˈsĭs [key], obstruction of an artery or vein by a blood clot (thrombus). Arterial thrombosis is generally more serious because the supply of oxygen and nutrition to an area of th...

Brachiopoda

(Encyclopedia)CE5 Internal anatomy of a lamp shell, Magellania, representative of the phylum Brachiopoda Brachiopoda brākēŏpˈədə [key], phylum of shelled sessile or sedentary marine animals, commonly know...