What process in photosynthis bears the most resemblance to chemiosmosis and oxidative phosphorylation?

noncylic photophosphorylation

During noncyclic photophosphorylation, the generation of ATP is coupled to a one-way flow of electrons from H2O to NADP+. We will now look at Photosystems I and II and their roles in noncyclic photophosphorylation.

 As photons are absorbed by pigment molecules in Photosystem II, excited electrons from the reaction center are picked up by the primary electron acceptor of the Photosystem II electron transport chain. During this process, Photosystem II splits molecules of H2O into 1/2 O2, 2H+, and 2 electrons. These electrons continuously replace the electrons being lost by the P680 chlorophyll a molecules in the reaction centers of the Photosystem II antenna complexes.

During this process, ATP is generated by the Photosystem II electron transport chain and chemiosmosis. According to the chemiosmosis theory, as the electrons are transported down the electron transport chain, some of the energy released is used to pump protons across the thylakoid membrane from the stroma of the chloroplast to the thylakoid interior space producing a proton gradient or proton motive force. As the accumulating protons in the thylakoid interior space pass back across the thylakoid membrane to the stroma through ATP synthetase complexes, this proton motive force is used to generate ATP from ADP and P.