BIOLOGY
HORMONES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Auxin
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Gibberellin
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Abscisic acid
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Cytokinin
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Detailed explanation-1: -Abscisic acid causes abscission, i.e., falling of leaves and fruits from the plant body.
Detailed explanation-2: -Final answer: The substance that triggers the fall of mature leaves and fruits from plants is abscisic acid.
Detailed explanation-3: -Ethylene (plant hormone responsible for ripening and senescence), Abscisic acid-ABA (stress hormone), and Auxin (growth hormone) all play a symphony and cause ‘Abscission-falling/separation of leaf tissue’ from the plant.
Detailed explanation-4: -Abscisic acid (ABA) is a general plant-growth inhibitor. It induces dormancy and prevents seeds from germinating; causes abscission of leaves, fruits, and flowers; and causes stomata to close. High concentrations of ABA in guard cells during periods of drought stress probably play a role in stomatal closure.
Detailed explanation-5: -Abscisic acid (ABA) is an important phytohormone regulating plant growth, development, and stress responses.