in terms of atp production, which process results in the most stored energy?

The process that results in the most stored energy in the form of ATP is aerobic respiration via oxidative phosphorylation (the electron transport chain in mitochondria).

Key idea

• In cells, ATP is made mainly by two mechanisms:
  • Substrate-level phosphorylation (in glycolysis and the citric acid cycle) produces only a small amount of ATP per glucose.

* **Oxidative phosphorylation** (part of aerobic respiration) uses the electron transport chain and a proton gradient to make the **vast majority** of ATP per glucose, so it yields the most stored energy.

Why oxidative phosphorylation wins

• Electrons from NADH and FADH₂ pass through the electron transport chain, pumping protons and creating a gradient across the inner mitochondrial membrane.

• ATP synthase then uses this gradient to generate large amounts of ATP from ADP and inorganic phosphate, far exceeding the ATP made directly in glycolysis or the Krebs cycle.

Very short classroom-style answer

In terms of ATP production, aerobic respiration’s oxidative phosphorylation step (electron transport chain) produces the most ATP and therefore results in the most stored energy.

TL;DR: Oxidative phosphorylation in aerobic respiration is the top ATP producer and thus stores the most energy in ATP.