Which one of the following plant hormones promotes stomatal closure during drought stress?
Abscisic acid
Auxin primarily regulates cell elongation and tropic growth; cytokinin promotes cell division and delays senescence; gibberellin promotes stem elongation, seed germination and flowering — none of these primarily controls stomatal closure under stress.
Abscisic acid (ABA) is known as the "stress hormone" of plants: under drought conditions it accumulates in leaves and triggers guard cells to lose turgor pressure, closing the stomata to reduce water loss through transpiration.
Hence, the answer is Abscisic acid.
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Which of the following is a type of nutrition?
I. Heterotrophic
II. Autotrophic
Which of the following are the 5 groups that plants are divided into?
Fungi are always
In which of the following plants root is the food storage organ?
Which of the following does NOT form an essential part of the process of photosynthesis?
