PLANTS
TRANSPORT IN PLANTS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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covering the shoot with a black plastic bag
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covering the shoot with a clear plastic bag
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removing the leaves from the shoot
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shining a bright light onto the shoot
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Detailed explanation-1: -The xylem cells make up a tube starting from the leaves, down the stem, till the roots. This creates a drinking straw from which the water travels from the roots to the leaves. Hence, if the rate of transpiration increase, the uptake of water from the roots and the shoots also increases.
Detailed explanation-2: -Answer and Explanation: The correct answer is (c) a rise in temperature. Water transport in plants is driven by evaporation.
Detailed explanation-3: -We may conclude that root water uptake depends on a number of factors such as soil hydraulic conductivity, rooting depth, root density distribution, soil moisture pressure head, demand set by the atmosphere (’potential’ transpiration) on the plant system, and the presence of a water table.
Detailed explanation-4: -A low root/shoot ratio will increase the transpiration as the supply of water through the roots will be not enough due to increased evaporation by a larger shoot system. Hence it will increase transpiration.
Detailed explanation-5: -Sunlight: During daytime the rate of transpiration is faster. This is because the stomata remain open to allow inward diffusion of carbon dioxide for the process of photosynthesis. During night time the stomata remain closed and thus transpiration hardly occurs.