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root pressure

noun, Botany
osmotic pressure within the cells of a root system that causes sap to rise through a plant stem to the leaves.
Origin of root pressure
1870-75 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for root pressure
  • Root growth pressure will be directly measured through the development of root pressure collars for lab and field use.
  • Develop root pressure system and secure reliable source of rootstock material for the greenhouse studies of hormone flux in apple.
root pressure in Science
root pressure  
Pressure produced in the roots of plants, causing exudation of sap from cut stems and guttation of water from leaves. The pressure is generated by the concentration of solutes in the xylem of the root and stem, which in turn causes water to move into the xylem by osmosis.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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