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root, in botany

(Encyclopedia)CE5 Longitudinal cross section of a root root, in botany, the descending axis of a plant, as contrasted with the stem, the ascending axis. In most plants the root is underground, but in epiphytes ...

sapwood

(Encyclopedia)sapwood, relatively thin, youngest, outer part of the woody stem of a tree, the part that conducts water and dissolved materials. In the cross section of a tree, the sapwood is recognizable by its tex...

coma, in medicine

(Encyclopedia)coma, in medicine, deep state of unconsciousness from which a person cannot be aroused even by painful stimuli. The patient cannot speak and does not respond to command. Coma is the result of damage t...

umbilical cord

(Encyclopedia)umbilical cord ŭmbĭlˈĭkəl [key], cordlike structure about 22 in. (56 cm) long in the pregnant human female, extending from the abdominal wall of the fetus to the placenta. Its chief function is t...

cattail

(Encyclopedia)cattail or reed mace, any plant of the genus Typha, perennial herbs found in almost all open marshes. The cattail (also called club rush) has long narrow leaves, sometimes used for weaving chair seats...

death

(Encyclopedia)death, cessation of all life (metabolic) processes. Death may involve the organism as a whole (somatic death) or may be confined to cells and tissues within the organism. Causes of death in human bein...

rhizome

(Encyclopedia)rhizome rīˈzōm [key] or rootstock, fleshy, creeping underground stem by means of which certain plants propagate themselves. Buds that form at the joints produce new shoots. Thus if a rhizome is cut...

Duarte, José Napoleón

(Encyclopedia)Duarte, José Napoleón dwärˈtā [key], 1925–90, president of El Salvador (1980–82, 1984–89). A Christian Democrat, he was mayor of San Salvador (1964–70). In 1972, Duarte was elected presid...

begonia

(Encyclopedia)begonia bĭgōnˈyə [key], any plant of the large genus Begonia and common name for the family Begoniaceae, mostly succulent perennial herbs of the American tropics cultivated elsewhere as bedding or...

thallophyte

(Encyclopedia)thallophyte, common name for members of the Thallophyta (or Thallobionta), a taxonomic group in some archaic classification systems that comprised algae, fungi, and lichens. The thallophytes were cons...