Explanation

Cyclic Photophosphorylation in performed by PS-I only. It involves a cyclic electron flow, in which the photoexcited electrons from PS-I are occasionally shunted back to chlorophyll via the electron transport chain. This cyclic electron flow supplements the supply of ATP but produces no NADPH. Non-cyclic Photophosphorylation involves both PS-I and PS-II. Splitting of water, release of oxygen and production of NADPH takes place during it.