MDCAT Biology MCQ #2462

During a severe drought, a plant prevents excessive water loss by closing its stomata. Which hormone mediates this stress response?

MDCAT Biology MCQ #2462

  1. Question 1

    Q1. During a severe drought, a plant prevents excessive water loss by closing its stomata. Which hormone mediates this stress response?

    • A) Auxin
    • B) Cytokinin
    • C) Ethene
    • D) Abscisic acid

    Answer: Abscisic acid

    Explanation: Abscisic acid (ABA) promotes stomatal closure during water stress. Ethene is tempting but is primarily involved in fruit ripening.