OBJECTIVE LIFE SCIENCE
PLANT PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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O2 concentration
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CO2 concentration
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Light
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Temperature
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Detailed explanation-1: -CO2 concentration: Stomata open at low concentration and close at high concentration. Water availability: Underwater stress condition stomata get close due to ABA hormone. Whereas concentration of oxygen does not have a great impact on stomatal movement. Thus, the correct answer is option A.
Detailed explanation-2: -Higher than ambient CO2 concentrations mediate a closure of stomatal pores in plants and conversely, low CO2 concentrations trigger opening of stomatal pores.
Detailed explanation-3: -Under drought, plants may also close their stomata to limit the amount of water that evaporates from their leaves. However, this strategy introduces new dilemmas. Because plants must exchange gases through their stomata, closing them prevents plants from taking up carbon dioxide (CO2).