PLANT PHYSIOLOGY
TRANSPORT IN PLANT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Water moves into roots by active transport, moves up the phloem to the leaves where some evaporates through the stomata-this creates a suction to pulls up more water behind it.
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Water moves into roots by osmosis, moves up the xylem to the leaves where some evaporates through the stomata-this creates a suction to pulls up more water behind it.
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Water moves into roots by diffusion, moves up the xylem to the leaves where some evaporates through the guard cells-this creates a suction to pulls up more water behind it.
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None of the above
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Detailed explanation-1: -In plants, the transpiration stream is the uninterrupted stream of water and solutes which is taken up by the roots and transported via the xylem to the leaves where it evaporates into the air/apoplast-interface of the substomatal cavity. It is driven by capillary action and in some plants by root pressure.
Detailed explanation-2: -Transpiration is a process that involves loss of water vapour through the stomata of plants. The loss of water vapour from the plant cools the plant down when the weather is very hot, and water from the stem and roots moves upwards or is ‘pulled’ into the leaves.
Detailed explanation-3: -The flow of water through the xylem from the roots to the leaf, against gravity, is called the transpiration stream.
Detailed explanation-4: -As transpiration occurs, it deepens the meniscus of water in the leaf, creating negative pressure (also called tension or suction). The tension created by transpiration “pulls” water in the plant xylem, drawing the water upward in much the same way that you draw water upward when you suck on a straw.
Detailed explanation-5: -The stream of water and solutes flowing from the roots to the leaves through the stem is called the transpiration stream. The water from this stream is then lost through transpiration from the leaves.