Which plant hormone is synthesized in shoot apical meristems and induces phototropic bending by stimulating cell elongation on the shaded side?
Answer and explanation
Correct answer: B. Auxin
- Step 1: Auxin (indole-3-acetic acid) promotes cell elongation and establishes apical dominance. Step 2. Light causes lateral redistribution of auxin to the shaded side, accelerating elongation and bending shoots toward light. Answer: Auxin. Why not the others: Abscisic acid maintains seed dormancy and closes stomata; cytokinin promotes cell division; ethylene induces fruit ripening.
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