Question

Number of ATP molecules required for
regeneration phase of' RuBP during synthesis of
1 glucose molecule
(a) 6 (b) 12
(c) 18 (d) 30

Answer 1

Answer : c) 18 ATP molecules

Explanation : 1 mol of CO2 molecule entering in Calvin cycle require 3 mol of ATP .Glucose is 6 carbon = 6×3 = 18 ATP

Answer 2

6 ATP molecules are required for the regeneration phase of RUBP during synthesis of one Glucose molecule.

● One ATP molecule is spent for recovery of RuBP.

● Consequently for an atom of glucose, 6 carbon dioxide particles should be fixed and 6 ATP particles will be required for recovering RuBP.

● In case of Kelvin cycle for the production of one Glucose molecule nearly 18 ATP molecules are to be spent.