PLANT PHYSIOLOGY
TRANSPORT IN PLANT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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I and II only
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I and III only
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II and III only
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I, II and III
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Detailed explanation-1: -The cohesion-tension theory (C-T theory) by Boehm (1893) and Dixon and Joly (1894) postulates that the water ascent in trees is exclusively due to the transpirational pull from continuous water columns in the xylem conduit running from the roots to the leafs.
Detailed explanation-2: -Guttation does not play a role in the ascent of sap.
Detailed explanation-3: -Hydrogen bonds cause water to be exceptionally attracted to each other. Therefore, water is very cohesive.
Detailed explanation-4: -The cohesion-tension hypothesis is the most widely-accepted model for movement of water in vascular plants. Cohesion-tension essentially combines the process of capillary action with transpiration, or the evaporation of water from the plant stomata.