In eukaryotes, oxidative phosphorylation occurs in the mitochondrion. The analogous structure used by bacteria to carry out oxidative phosphorylation is the:

In eukaryotic cells, oxidative phosphorylation occurs within the mitochondria, specifically in the inner mitochondrial membrane. This process involves the electron transport chain and ATP synthase to produce ATP from the energy released during the transfer of electrons.

In bacteria, which lack mitochondria, oxidative phosphorylation occurs across their plasma membrane. This membrane contains protein complexes that function similarly to those in the mitochondrial inner membrane, facilitating the electron transport chain and chemiosmosis. As protons are pumped across the plasma membrane and create a proton gradient, ATP synthase in the membrane uses this gradient to generate ATP.

The cell wall and nuclear membrane do not have roles in energy generation or the process of oxidative phosphorylation. The cytoplasm does contain some of the components necessary for cellular metabolism but does not host the machinery for oxidative phosphorylation itself; that takes place at the plasma membrane in bacteria. This is why the plasma membrane is the correct structure where oxidative phosphorylation occurs in prokaryotes.