Protons are pumped into the thylakoid lumen creating a gradient
Explanation:
Photosynthetic electron transport is helpful in the conversion of solar energy into chemical energy in the process of photosynthesis through transferring electrons sequentially from [tex]H_2O[/tex] through Photosystem II and Photosystem I to NADP+.
Cyclically flowing electrons generate ATP molecules, because after passing down the first step of the electron transport chain protons are pumped into the thylakoid lumen, and establishes a gradient in between.
However, cyclic electron flow does not involve in the formation of NADPH, nor does it involve in the splitting of water or production of oxygen.