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prickly heat

(Encyclopedia)prickly heat (miliaria), inflammatory skin eruption due to obstruction of the sweat glands by keratin, the substance that forms the horny cells of the epidermis. It consists of blisterlike elevations ...

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...

Tsien, Roger Yonchien

(Encyclopedia)Tsien, Roger Yonchien, 1952–2016, American biochemist, b. New York City, Ph.D. Cambridge, 1977. Tsien was a researcher at Cambridge (1977–81) and a professor at the Univ. of California, Berkeley (...

toxin

(Encyclopedia)toxin, poison produced by living organisms. Toxins are classified as either exotoxins or endotoxins. Exotoxins are a diverse group of soluble proteins released into the surrounding tissue by living ba...

synapse

(Encyclopedia)synapse sĭnˈăps [key], junction between various signal-transmitter cells, either between two neurons or between a neuron and a muscle or gland. A nerve impulse reaches the synapse through the axon,...

testis

(Encyclopedia)testis tĕsˈtĭkəl [key], one of a pair of glands that produce the male reproductive cells, or sperm. In fetal life the testes develop in the abdomen, then descend into an external sac, the scrotum....

iris, in botany

(Encyclopedia)CE5 Red iris, Iris fulva iris, common name for members of the genus Iris of the Iridaceae, a family of perennial herbs that includes the crocuses, freesias, and gladioli. The family is characteriz...

Harrison, Ross Granville

(Encyclopedia)Harrison, Ross Granville, 1870–1959, American biologist and anatomist, b. Germantown, Pa., Ph.D. Johns Hopkins, 1894. He went to Yale as professor of comparative anatomy in 1907 and held various hon...

amyloplast

(Encyclopedia)amyloplast ămˈəlōplăstˌ [key], also called leucoplast, a nonpigmented organelle, or plastid, occurring in the cytoplasm of plant cells. Amyloplasts transform glucose, a simple sugar, into starch...

Schultze, Max Johann Sigismund

(Encyclopedia)Schultze, Max Johann Sigismund mäks yōˈhän zēˈgĭsmo͝ond sho͝olˈtsə [key], 1825–74, German biologist, director of the Anatomical Institute at Bonn from 1859. He established that the cells ...