Compare the cyclic and noncyclic electron transport pathways of photosynthesis.

Both cyclic and noncyclic electron transport involve photosynthetic pigments embedded in the thylakoid membranes as well as the flow of electrons down an electron transport chain resulting in the generation of ATP via chemiosmosis. Cyclic electron transport does not involve the reduction of NADP⁺. Instead, electrons flow in a cyclical pathway from photosystem I to the electron transport chain and back to photosystem I. By contrast, noncyclic electron flow involves the linear flow of electrons from water to photosystem II, down an electron transport chain to photosystem I, and finally to NADP⁺. Consequently, the noncyclic pathway results in the formation of O₂, while the cyclic pathway does not.