The diagram shows coupling A→B with ATP hydrolysis. Why is the coupled process spontaneous?
- A
Enzymes lower the ΔG of A→B
- B
ATP hydrolysis decreases entropy and thus ΔG
- C
ATP raises temperature, driving the reaction
- Dcheck_circle
The summed ΔG is negative because ATP hydrolysis is more exergonic than A→B is endergonic
Explanation
Coupled reactions sum their ΔG. If ATP hydrolysis releases more energy than the endergonic step requires, the net ΔG is negative and the process proceeds.