PLANTS
PLANT RESPONSES TO STIMULI
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It grows away from the light
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It grows towards the trees
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It grows towards the roots
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It grows towards the light
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Detailed explanation-1: -One important light response in plants is phototropism, which involves growth toward-or away from-a light source. Positive phototropism is growth towards a light source; negative phototropism is growth away from light.
Detailed explanation-2: -A plants response to light has been well documented and studied. It is known to be due to differential elongation of the cells in the plant stem. Stem cells away from the light elongate in response to special auxins (growth hormones) causing the plant stem to bend towards the light.
Detailed explanation-3: -"Even mature plants bend toward the strongest light. They do this by elongating the cells of the stem on the side that is farthest from the light. This type of light-oriented growth is called phototropism, ” explains Prof.
Detailed explanation-4: -When light falls on one side of the plant, the auxins generally diffuse towards the shaded side of the shoot. This stimulates the cells in the shaded area to grow longer than the corresponding cells of the illuminated region. This results in the curvature of the plant stem tip towards the light.
Detailed explanation-5: -It grows because the auxin causes the cells to elongate on the shaded side, so this side grows more. This unequal growth of the two sides, results in the growth of the stem towards the light. If lit from above, the plant will grow upwards. Auxins have the opposite effect on root cells.