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gonadotropic hormone

(Encyclopedia)gonadotropic hormone gōˌnădətrŏpˈĭk [key] or gonadotropin, any one of three glycoprotein (see protein) hormones released by either the anterior pituitary gland or the placenta (the organ in whi...

Pontormo, Jacopo da

(Encyclopedia)Pontormo, Jacopo da yäˈkōpō dä pōntôrˈmō [key], 1494–1556, Florentine painter, one of the creators of mannerism. His real name was Jacopo Carrucci. He studied with Andrea del Sarto, Leonard...

sonar

(Encyclopedia)sonar sōˈnär [key], device used underwater for locating submerged objects and for submarine communication by means of sound waves. The term sonar is an acronym for sound navigation ranging. The mai...

wetlands

(Encyclopedia)wetlands, low-lying ecosystem where the water table is always at or near the surface. It is divided into estuarine and freshwater systems, which may be further subdivided by soil type and plant life i...

larva, in zoology

(Encyclopedia)larva, independent, immature animal that undergoes a profound change, or metamorphosis, to assume the typical adult form. Larvae occur in almost all of the animal phyla; because most are tiny or micro...

rain

(Encyclopedia)rain, precipitation in liquid form. It consists of drops of water falling from clouds; if the drops are very small, they are collectively termed drizzle. Rain plays a key role in the hydrologic, or wa...

Nietzsche, Friedrich Wilhelm

(Encyclopedia)Nietzsche, Friedrich Wilhelm frēˈdrĭkh vĭlˈhĕlm nēˈchə [key], 1844–1900, German philosopher, b. Röcken, Prussia. The son of a clergyman, Nietzsche studied Greek and Latin at Bonn and Leipz...

louse

(Encyclopedia)louse, common name for members of either of two distinct orders of wingless, parasitic, disease-carrying insects. Lice of both groups are small and flattened with short legs adapted for clinging to th...

feast

(Encyclopedia)feast, commemorative banquet symbolizing communal unity. Generally associated with primitive rituals and later with religious practices, feasts may also commemorate such events as births, marriages, h...

reproductive system

(Encyclopedia)CE5 Reproductive system reproductive system, in animals, the anatomical organs concerned with production of offspring. In humans and other mammals the female reproductive system produces the femal...