Which plant hormone promotes stomatal closure during water deficit stress to minimize transpiration water loss?
Answer and explanation
Correct answer: C. Abscisic acid (ABA)
- Step 1: Under drought stress, roots and mesophyll synthesize abscisic acid (ABA). Step 2. ABA binds guard cell receptors, triggering potassium ion efflux and water loss, closing stomata. Answer: Abscisic acid (ABA). Why not the others: Auxins and gibberellins stimulate growth and elongation.
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