Here's why:
* Electron Transport Chain: This chain of protein complexes uses the energy from electrons, passed down from the breakdown of glucose (glycolysis and the Krebs cycle), to pump protons across the inner mitochondrial membrane. This creates a proton gradient.
* ATP Synthase: This enzyme utilizes the potential energy stored in the proton gradient to generate ATP from ADP and inorganic phosphate. This process is called oxidative phosphorylation and is highly efficient, producing the majority of ATP in eukaryotic cells.
While glycolysis does produce a small amount of ATP (2 molecules per glucose), it's a relatively inefficient process compared to oxidative phosphorylation, which can produce up to 38 molecules of ATP per glucose molecule.
