BIOLOGY
HORMONES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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opposite of the light source
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on the same side as the light source
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Either A or B
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None of the above
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Detailed explanation-1: -Phototropisms. In a stem, the shaded side contains more auxin and grows longer, which causes the stem to grow towards the light. The plant does NOT bend towards the light. It grows because the auxin causes the cells to elongate on the shaded side, so this side grows more.
Detailed explanation-2: -Auxins also play a part in phototropism, an occurrence that involves plants bending or moving away from light. The shoot tip is responsible for directional movement by the plant in response to sunlight, as this is the area where auxins can be found.
Detailed explanation-3: -More auxin is transported down the shady side, and less auxin is transported down the illuminated side. Auxin promotes cell elongation, causing the plant to grow more on the shady side and bend in the direction of the light source.
Detailed explanation-4: -Auxin hormone has opposite effect on the roots of a plant. That is why when sunlight falls on the right side of the roots, auxin hormone collects on the left side and hampers their growth from that side. That is why, roots bend towards left.