In non-cyclic electron transport, which components are required and what is the electron flow?

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Multiple Choice

In non-cyclic electron transport, which components are required and what is the electron flow?

Non-cyclic electron transport requires both photosystems to convert light energy into NADPH while also pumping protons to make ATP and releasing oxygen from water. The process starts when light excites PSII, which pulls electrons from water and sends them into the electron transport chain through plastoquinone and the cytochrome b6f complex, driving a proton gradient. Those electrons are then shuttled to PSI via plastocyanin. Light energizes the electrons again in PSI, enabling their transfer through ferredoxin to NADP+ reductase, forming NADPH. Because electrons ultimately end at NADP+, this flow is non-cyclic. The involvement of both photosystems is essential; using only one would not efficiently produce NADPH and would not support the full transfer that ends with NADP+ reduction.

Non-cyclic electron transport requires both photosystems to convert light energy into NADPH while also pumping protons to make ATP and releasing oxygen from water. The process starts when light excites PSII, which pulls electrons from water and sends them into the electron transport chain through plastoquinone and the cytochrome b6f complex, driving a proton gradient. Those electrons are then shuttled to PSI via plastocyanin. Light energizes the electrons again in PSI, enabling their transfer through ferredoxin to NADP+ reductase, forming NADPH. Because electrons ultimately end at NADP+, this flow is non-cyclic. The involvement of both photosystems is essential; using only one would not efficiently produce NADPH and would not support the full transfer that ends with NADP+ reduction.

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