BIOLOGY
HORMONES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The lights must have emitted far-red light.
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It was due to phototropism.
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They must have been long-day plants.
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They must have been long-night plants.
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Detailed explanation-1: -An Alaskan trapper worried about being attacked by grizzly bears left the lights on in his cabin all the time. Plants just outside the cabin flowered a month early. Which of the following best explains this? They must have been long-day plants.
Detailed explanation-2: -Plants have evolved a wide variety of responses that allow them to adapt to the variable environmental conditions in which they find themselves growing. One such response is the phototropic response-the bending of a plant organ toward (stems and leaves) or away from (roots) a directional blue light source.
Detailed explanation-3: -What happens immediately after a phytochrome is activated by light? Ca2+ channels are opened and guanylyl cyclase is activated.
Detailed explanation-4: -Summary. The plant hormone ABA is a critical component of the stress acclimation mechanism in many plants. Plants produce ABA in response to a wide array of water associated stresses such as drought, salinity, cold and heat.
Detailed explanation-5: -Removal of the apical bud removes auxin from the plant, which has the effect of inhibiting lateral growth and allowing cytokinins to flow more freely in the plant, thereby encouraging lateral growth.