PLANT PHYSIOLOGY
PHOTOSYNTHESIS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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NADP+ reductase
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rubisco
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ATP synthase
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None of the above
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Detailed explanation-1: -(a) An enzyme, RuBP carboxylase, catalyzes both the joining of carbon dioxide with RuBP and the joining of oxygen gas with RuBP. The two molecules are alternative substrates that compete with each other for the same active site on the enzyme.
Detailed explanation-2: -CO2 combines with RuBP in the presence of enzyme RuBisCO to form 3-PGA.
Detailed explanation-3: -Rubisco can bind to either carbon dioxide or oxygen depending on environmental conditions. Binding to carbon dioxide and initiation of the Clavin cycle is favored at low temperatures and at a high carbon dioxide-to-oxygen ratio.
Detailed explanation-4: -The enzyme Rubisco (RuBP carboxylase/oxygenase) attaches CO2 to RuBP to form a highly unstable 6-carbon intermediate that immediately breaks down into 2 3-carbon sugars, 3PG.