ANIMAL PHYSIOLOGY
NERVOUS SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a plant’s ability to reproduce
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uptake of water through the plant’s root system
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defense from possible predators
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a plant’s ability to respond to its environmental conditions
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Detailed explanation-1: -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-2: -In a plant seedling exposed to light on only one side, auxin produced in the tip moves to the lighted side and inhibits growth of cells there.
Detailed explanation-3: -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.
Detailed explanation-4: -Phytochrome stimulates plant growth toward red light via the hormonecytokinin, which promotes cell division, and gibberellin, which promotes stem elongation. Cytokinin is activated by the Pfr form of phytochrome, thus causing cell division in the apical meristems that are in the presence of red light.
Detailed explanation-5: -The movement of plant parts in response to sunlight is termed as phototropism. Complete Answer: When a plant receives sunlight from only one direction, the shoot of that plant bends in the direction of the sunlight. This is because of the hormone auxin which accumulates in the side where sunlight is not present.