Question

The below diagram is the cyclic series of reactions that occurs during carbon fixation stage of photosynthesis –

Carbon dioxide is taken into the cycle at state A.

Hydrogen from reduced hydrogen acceptor is used at stage B.

Energy from ATP is used to drive stages C.

The substance formed at position Y is D.

If one molecule of substance Y is released per cycle, how many E times must the cycle turn for one molecule of sucrose (C₁₂H₂₂O₁₁) to be built up at position Z?

• A. A – 4; B – 2; C – 2 and 3; D – 3-carbon sugar; E – 4
• B. A – 3; B – 3; C – 1 and 2; D – pyruvate acid, E – 2
• C. A – 2; B – 4; C – 3 and 4; D – glucose-1-phosphate; E – 8
• D. A – 1; B – 1; C – 2 and 4; D – citric acid; E – 12

Answer 1

Answer: (A)

A – 4; B – 2; C – 2 and 3; D – 3-carbon sugar; E – 4