thermoregulation in plants | Heat shock protein | Class 12 Biology
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thermoregulation in plants | Heat
thermoregulation in plants | Heat shock protein | Class 12 Biology
About This Video!
THERMOREGULATION
Control systems operate in organisms to cope with environmental stresses including temperature extremes.
Adaptations in Plants to Low and High Temperature High Temperature : High temperature denatures the enzymes and damages the metabolism, therefore, it harms or kills the plants. Plants use evaporative cooling to manage with high
temperature. Hot and dry weather, however, causes water deiciency resulting in closing of stomata, thus plants sufer in such conditions. Most plants have adapted to survive in heat stress as the plants of temperate regions face the stress of 40°C and above temperature. The cells of these
plants synthesize large quantities of special proteins called heat-shock proteins. These proteins embrace enzymes and other proteins thus help to prevent denaturation.
Low Temperature : In low temperature the luidity of the cell membrane is altered, because lipids of the membrane become locked into crystalline structures, which afects the transport of the
solutes. The structure of the membrane proteins is also afected. Plants respond to cold stress by increasing proportion of unsaturated fatty acids, which help membrane to maintain structure at
low temperature by preventing crystal formation. This adaptation requires time because of this reason rapid chilling of plants is more stressful than gradual drop in air temperature.Freezing temperature causes ice crystal formation. The coninement of ice formation around cell
wall does not afect as badly and plants survive, however, formation of ice crystals within protoplasm perforates membranes and organelles hence killing the cells. The plants native to cold region such
as oaks, maples, roses and other plants have adapted to bring changes in solutes composition of the cells, which causes cytosol to super cool without ice formation, although ice crystals may form in the cell walls
About This Video!
THERMOREGULATION
Control systems operate in organisms to cope with environmental stresses including temperature extremes.
Adaptations in Plants to Low and High Temperature High Temperature : High temperature denatures the enzymes and damages the metabolism, therefore, it harms or kills the plants. Plants use evaporative cooling to manage with high
temperature. Hot and dry weather, however, causes water deiciency resulting in closing of stomata, thus plants sufer in such conditions. Most plants have adapted to survive in heat stress as the plants of temperate regions face the stress of 40°C and above temperature. The cells of these
plants synthesize large quantities of special proteins called heat-shock proteins. These proteins embrace enzymes and other proteins thus help to prevent denaturation.
Low Temperature : In low temperature the luidity of the cell membrane is altered, because lipids of the membrane become locked into crystalline structures, which afects the transport of the
solutes. The structure of the membrane proteins is also afected. Plants respond to cold stress by increasing proportion of unsaturated fatty acids, which help membrane to maintain structure at
low temperature by preventing crystal formation. This adaptation requires time because of this reason rapid chilling of plants is more stressful than gradual drop in air temperature.Freezing temperature causes ice crystal formation. The coninement of ice formation around cell
wall does not afect as badly and plants survive, however, formation of ice crystals within protoplasm perforates membranes and organelles hence killing the cells. The plants native to cold region such
as oaks, maples, roses and other plants have adapted to bring changes in solutes composition of the cells, which causes cytosol to super cool without ice formation, although ice crystals may form in the cell walls
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