HORTICULTURE SCIENCE
ULTRA STRUCTURE OF PLANT CELLS AND ORGANS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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some plants (eg:eucalypts) are able to change the orientation of leaves so they hang vertically during hot weather
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In extreme heat plants increase transpiration this leads to a loss of water pressure inside plant cells and leaves wilt
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stomata open, loss of water by transpiration
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some eucalypts can drop leaves during dry season
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Detailed explanation-1: -The action of turgor pressure on extensible cell walls is usually said to be the driving force of growth within the cell. An increase of turgor pressure causes expansion of cells and extension of apical cells, pollen tubes, and other plant structures such as root tips.
Detailed explanation-2: -Leaf turgor pressure in hydrated leaves (∼0.6 megapascal) decreased to zero upon wilting.
Detailed explanation-3: -Turgor pressure in plants plays a key role in processes such as growth, development, mechanical support, signalling, flowering and stress response. Turgor pressure is an ideal means in plant cells through which the energy content of water molecules (water potential) can be adjusted quickly, within seconds.
Detailed explanation-4: -turgor, Pressure exerted by fluid in a cell that presses the cell membrane against the cell wall. Turgor is what makes living plant tissue rigid. Loss of turgor, resulting from the loss of water from plant cells, causes flowers and leaves to wilt.