GROWTH DEVELOPMENT CHILD
GROWTH AND DEVELOPMENT
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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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cytokinin
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ethylene
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Detailed explanation-1: -Unequal distribution of auxin causes phototropism . It causes the plant growth either away or towards the light, based on which part receives light. Auxins are present in higher quantities on the shaded side of a stem. Since auxins promote stem elongation, the shaded part grows taller.
Detailed explanation-2: -Auxins have the opposite effect in roots. This is negative phototropism. In a root the shaded side contains more auxin but grows less. This causes the root to bend away from the light.
Detailed explanation-3: -Auxins will move downward due to gravity and laterally, away from light. Cells grow more in areas of the plant where auxins are highly concentrated.
Detailed explanation-4: -Light imposes a high degree of control on auxin levels and distribution but its action is not restricted to these processes; light also moderates the sensitivity to auxin within the cell. By imposing control on the nuclear auxin response pathway, light can dampen or amplify the response to auxin.