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Question
Under what conditions are C4 plants superior to C3?
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Solution
C4 plants are superior to C3 plants under the following conditions:
C4 plants can perform photosynthesis at low CO2 concentrations. C4 plants show saturation at about 360 L – 1, while C3 plants show saturation only beyond 450 L – 1. This means that the availability of CO2 is a limiting factor for C3 plants; which is not the case with C4 plants. C4 plants show a higher temperature optimum but C3 plants show a lower temperature optimum. So, C4 plants can carry on photosynthesis even at high temperatures; which is not the case with C3 plants. C4 plants are not affected by high oxygen levels in the atmosphere because the plants are not affected by Kranz’s anatomy. Kranz’s anatomy ensures that photorespiration does not take place in C4 plants. But this is not the case with C3 plants.
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