Question

Read the given statements and select the correct option.
Statement 1 : Carboxylation is the most crucial step of Calvin cycle where $C{O}_2$ is utilised for the carboxylation of $RuBP$.
Statement 2: Carboxylation is catalysed by the enzyme $RuBisCO$ which results in the formation of two molecules of $3PGA$.

• A. Both statements 1 and 2 are correct
• B. Statement 1 is correct but statement 2 is incorrect
• C. Statement 1 is incorrect but statement 2 is correct
• D. Both statements 1 and 2 are incorrect

Answer 1

Answer: (A)

Carboxylation is the fixation of $C{O}_2$ into a stable organic intermediate. It is the most crucial step of Calvin cycle where $C{O}_2$ is utilised for the carboxylation of $RuBP$ through the use of $ATP$ and $NADPH$ generated by the light reactions. This reaction is catalysed by enzyme $RuBisCO$ which results in the formation of two molecules of $3$-phosphoglyceric acid or $PGA$, which is the first stable product of photosynthesis.