Explain the origin, location, and function of the proton gradient in the process of photosynthesis. What will be an ideal response?

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The proton gradient is established in the thylakoid lumen as electrons flow down the photosynthetic
electron transport chain. As the electrons lose energy some of that energy is used to pump protons
across the thylakoid membrane into the lumen. As the protons accumulate, they form a gradient, with
the proton concentration in the lumen higher than in the stroma. Eventually the protons flow
“downhill” through the ATP synthase complex in the thylakoid membrane. The exergonic process of
diffusion down this gradient is used to power the endergonic process of ATP synthesis