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pineal gland

(Encyclopedia)pineal gland pĭnˈeəl [key], small organ (about the size of a pea) situated in the brain. Long considered vestigial in humans, the structure, which is also called the pineal body or the epiphysis, i...

selection

(Encyclopedia)selection. In Darwinism, the mechanism of natural selection is considered of major importance in the process of evolution. Popular formulations sometimes envisage a struggle for existence in which dir...

heredity

(Encyclopedia)heredity, transmission from generation to generation through the process of reproduction in plants and animals of factors which cause the offspring to resemble their parents. That like begets like has...

record player

(Encyclopedia)record player or phonograph, device for reproducing sound that has been recorded as a spiral, undulating groove on a disk. This disk is known as a phonograph record, or simply a record (see sound reco...

Edwards, Sir Robert Geoffrey

(Encyclopedia)Edwards, Sir Robert Geoffrey, 1925–2013, British physiologist, Ph.D. Edinburgh Univ., 1955. In 1963 he became a research fellow at Cambridge. He was associated with the university until his death, a...

De Vinne, Theodore Low

(Encyclopedia)De Vinne, Theodore Low də vĭnˈē [key], 1828–1914, American printer, b. Stamford, Conn. He learned his trade in the office of the Newburgh (N.Y.) Gazette and in 1848 entered the shop of Francis H...

Euglenophyta

(Encyclopedia)Euglenophyta yo͞oˌglənŏfˈətə [key], small phylum (division) of the kingdom Protista, consisting of mostly unicellular aquatic algae. Most live in freshwater; many have flagella and are motile. ...

Mastigophora

(Encyclopedia)Mastigophora măsˌtĭgŏfˈərə [key], phylum of unicellular heterotrophic protozoans of the kingdom Protista. Most of the approximately 1,500 species of Mastigophora are propelled by one or more fl...

physiology

(Encyclopedia)physiology fĭzēŏlˈəjē [key], study of the normal functioning of animals and plants during life and of the activities by which life is maintained and transmitted. It is based fundamentally on the...

vegetative propagation

(Encyclopedia)vegetative propagation, the ability of plants to reproduce without sexual reproduction, by producing new plants from existing vegetative structures. Some plants, such as the Canada thistle and most ba...