EVOLUTION
DARWIN’S THEORY OF NATURAL SELECTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Flowers with short root systems
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Flowers with average root systems
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Flowers with the longest root systems
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Detailed explanation-1: -The allocation of photosynthate in roots and the rhizosphere is inhibited under severe drought conditions. Thus, the inhibition of root growth will in turn reduce water and nutrient uptake, ultimately influencing both biomass accumulation and grain yield.
Detailed explanation-2: -Plants and trees couldn’t thrive without capillary action. Capillary action helps bring water up into the roots. With the help of adhesion and cohesion, water can work it’s way all the way up to the branches and leaves.
Detailed explanation-3: -The immediate response of plants on being exposed to drought stress is stomatal closure. However, stomatal closure not only diminishes water loss through transpiration but also reduces CO 2 and nutrient uptake, and hence alters metabolic pathways such as photosynthesis 55.
Detailed explanation-4: -The scarlet globe mallow (Sphaeralcea coccinea) is a drought-escaping plant with natural drought tolerance. Some of its natural adaptations include silver-gray hairs that protect against drying; a deep root system; and having seeds that only germinate when conditions are favorable.