In the C4 photosynthetic pathway, the primary CO2 acceptor is: MCQ with Answer and Explanation

In the C4 photosynthetic pathway, the primary CO2 acceptor is:
A. Oxaloacetate (OAA)
B. Phosphoenolpyruvate (PEP)
C. Malate
D. Ribulose-1,5-bisphosphate (RuBP)
Answer: Option B
Solution (By JKExamLibrary)
In C4 plants, the initial fixation of CO2 occurs in the mesophyll cells. The primary CO2 acceptor is a 3-carbon compound, phosphoenolpyruvate (PEP). The enzyme PEP carboxylase catalyzes the reaction, forming a 4-carbon compound, oxaloacetate (OAA). In C3 plants, the primary acceptor is RuBP, a 5-carbon compound, and the enzyme is RuBisCO.

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Correct Answer: Option D


Explanation:
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Correct Answer: Option B


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