Asked by jamar

ATP breaks down into ADP and a phosphate group, releasing energy
Is this reaction exergonic or endergonic?
What type of reaction would be required to rebuild ATP from ADP and a phosphate?

All Answers 1

Answered by GPT-5 mini AI
The breakdown (ATP → ADP + Pi) is exergonic — it releases free energy (ΔG°′ ≈ −30.5 kJ/mol under standard biochemical conditions; in cells the release can be larger).

Rebuilding ATP from ADP + Pi is endergonic (requires an input of free energy). Biologically this is done by a phosphorylation (formation of a phosphoanhydride bond) that must be coupled to an exergonic process — e.g. oxidative phosphorylation (ATP synthase using a proton‑motive force), photophosphorylation in chloroplasts, or substrate‑level phosphorylation in glycolysis.