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Bartholin

(Encyclopedia)Bartholin bärˈtōlēn [key], renowned Scandinavian family. Kaspar Bartholin, 1585–1629, b. Sweden, was a Danish physician. He was professor of medicine and later of theology at the Univ. of Copenh...

cuttlefish

(Encyclopedia)cuttlefish, common name applied to cephalopod mollusks that have 10 tentacles, or arms, 8 of which have muscular suction cups on their inner surface and 2 that are longer and can shoot out for graspin...

neoteny

(Encyclopedia)neoteny nēŏtˈənē [key], in biology, sexual maturity reached in the larval stage of some animals. Certain environmental conditions can inhibit the completion of metamorphosis; low temperature or l...

molting

(Encyclopedia)molting, periodical shedding and renewal of the outer skin, exoskeleton, fur, or feathers of an animal. In most animals the process is triggered by secretions of the thyroid and pituitary glands. Near...

musk deer

(Encyclopedia)musk deer, small, antlerless deer, Moschus moschiferus, found in wet mountain forests from Siberia and Korea to the Himalayas. In summer it ranges up to 8,000 ft (2,400 m). It is from 20 to 24 in. (50...

Addison's disease

(Encyclopedia)Addison's disease [for Thomas Addison], progressive disease brought about by atrophy of the outer layer, or cortex, of the adrenal gland; it is also called chronic adrenocortical insufficiency. The de...

Steno, Nicolaus

(Encyclopedia)Steno, Nicolaus nēls stānˈsən [key], 1638–86, Danish anatomist, geologist, and Roman Catholic prelate. He lived principally in Copenhagen, Paris, and Florence. He investigated the heart, brain, ...

aldosterone

(Encyclopedia)aldosterone ălˌdōstĭrōnˈ [key], steroid secreted by the cortex of the adrenal gland. It is the most potent hormone regulating the body's electrolyte balance. Aldosterone acts directly on the kid...

urethra

(Encyclopedia)urethra yo͝orēˈthrə [key], canal in most mammals that carries urine from the bladder to the outside of the body; in the male it also serves as a genital duct. The urethra is about 11⁄2 in. long ...

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 ...