Question

Question 39
Six turns of Calvin cycle are required to generate one mole of glucose. Explain.

Answer 1

Ribulose 5 phosphate is a five carbon compound which accepts atmospheric $C{O}_2$ in presence of RuBisCo and form 2 molecules of 3PGA, $a^{3c}$ carbon compound. It uses 3 ATP and 2 NADPH to fix one molecule of $C{O}_2$ per cycle of Calvin.
So, to fix 6 $C{O}_2$ molecules to form 6 carbon compound glucose 6 cycles are required as mentioned below.

$\begin{array}{cc}In& Out\\ SixC{o}_2& Oneglucose\\ & molecule\left(C_6{H}_{12}{O}_6\right)\\ 18ATP& 18ADP\\ 12NADPH& 12NADP\end{array}$