Callose

callose

[′ka‚lōs]

(biochemistry)

A carbohydrate component of plant cell walls; associated with sieve plates where calluses are formed.

(biology)

Having hardened protuberances, as on the skin or on leaves and stems.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Callose

 

a polysaccharide, insoluble in water, contained in plants and consisting of glucose-molecule residues joined in a spiral chain (as opposed to cellulose, in which the glucose molecules are joined in a straight chain).

Callose lines the tubules of the sievelike layers of phloem; asthese tubules age, the amount of callose increases and the tubulesbecome plugged and cease functioning. When a plant is injured, callose is deposited on the cell walls of the parenchyma, forminga callus. Callose is also found in the cell walls of some algae andfungi.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.