Medullary Ray(redirected from Medullary rays)
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medullary ray[me′dəl·ə·rē ‚rā]
An extension of pith between vascular bundles in the plant stem. Also known as pith ray.
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 It might be outdated or ideologically biased.
a single or polystichous layer of parenchymal cells that intersect the lignin and bast of stems and roots of dicotyledonous plants. Medullary rays serve a storage function and transport matter in a horizontal direction.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
medullary ray, pith ray
In a cross section of a tree or log, one of the ribbons of tissue extending radially from the pith; may vary from microscopic to 4 in. (10 cm) or more in oak; used to store and transport food horizontally within the tree.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.