PHOTOSYNTHESIS
C 4 PHOTOSYNTHESIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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to avoid Photorespiration by oxygen
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to keep oxygen deposits high
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to make water vapor exit the through the stomata
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Detailed explanation-1: -Note: C4 plants avoid photorespiration because they have the enzyme called PEP during the first step of carbon fixation. Hence the carbon dioxide regenerated during photorespiration is recycled through PEP.
Detailed explanation-2: -The malate and Asp, resulting from the rapid conversion of OAA, are the organic acids delivered to the sites of carbon reduction in the bundle-sheath cells of the leaf, where they are decarboxylated, with the released CO2 used to make carbohydrates.
Detailed explanation-3: -C4 photosynthesis is thought to have evolved in response to environments where the oxygenation reaction of rubisco was high (Sage et al., 2012), as a mechanism to reduce photorespiration by increasing CO2 concentration at the site of carboxylation.
Detailed explanation-4: -C4 species of Flaveria, a dicotyledonous genus that has been used to examine the evolution of C4 photosynthesis for more than 25 years, also show high levels of malate production during CO2 fixation, as well as high activity of NADP-ME in leaf tissue.