Question

The form of carbon used for carboxylation of phosphoenol pyruvate in $C_4$ plants is

• A. $H_{2}C{O}_3$
• B. $C_2{H}_4$
• C. $C{H}_4$
• D. $HC{O}_3^{-}$.

Answer 1

Answer: (D)

$HC{O}_3^{-}$.

A) The ionised form of $H_2{CO}_3$ is used. It cannot be used directly.
B) Ethane is not used in the carboxylation of phosphoenolpyruvate.

C) Methane is not used in the carboxylation of phosphoenolpyruvate.
D) ${HCO}_3^{-}$ is used for the carboxylation of phosphoenol pyruvate in $C_4$ plants.
So the correct answer is '${HCO}_3^{-}$'.