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epithelium

(Encyclopedia)epithelium ĕpˌəthēˈlēəm [key], sheet of tissue that covers or lines the external and internal body surfaces. The epithelium is closely packed, has little intercellular material, and is lacking ...

corm

(Encyclopedia)corm, short, thickened underground stem, usually covered with papery leaves. A corm grows vertically, producing buds at the upper nodes and roots from the lower surface. Corms serve as organs of food ...

herbaceous plant

(Encyclopedia)herbaceous plant hûrbāˈshəs [key], plant whose stem is soft and green and shows little growth of wood. The term is used to distinguish such plants from woody plants. Herbaceous plants, or herbs, a...

Mezozoa

(Encyclopedia)Mezozoa mĕzˈəzōˌə, mēˈzə– [key], name of an animal subkingdom and also of the subkingdom's only phylum. The mezozoans are simple parasitic marine wormlike animals of only 20 to 30 cells, wh...

transpiration

(Encyclopedia)transpiration, in botany, the loss of water by evaporation in terrestrial plants. Some evaporation occurs directly through the exposed walls of surface cells, but the greatest amount takes place throu...

pus

(Encyclopedia)pus, thick white or yellowish fluid that forms in areas of infection such as wounds and abscesses. It is constituted of decomposed body tissue, bacteria (or other micro-organisms that cause the infect...

runner

(Encyclopedia)runner or stolon, slender, creeping stem capable of taking root where its nodes touch the ground and thereby producing new shoots. The runner itself usually dies at the end of the season, leaving inde...

rust, in botany

(Encyclopedia)rust, in botany, name for various parasitic fungi of the order Uredinales and for the diseases of plants that they cause. Rusts form reddish patches of spores on the host plant. About 7,000 species ar...

cyclosis

(Encyclopedia)cyclosis sīklōˈsĭs [key], streaming of cytoplasm within a living cell without deformation of the external cell membrane. In some plant cells there is a rapid rotatory cytoplasmic movement, which i...

Equisetophyta

(Encyclopedia)Equisetophyta ĕkˌwəsətŏfˈətə [key], small division of the plant kingdom consisting of the plants commonly called horsetails and scouring rushes. Equisetum, the only living genus in this divisi...