<P> Similar to the electron transport chain , the light - dependent reactions of photosynthesis pump protons into the thylakoid lumen of chloroplasts to drive the synthesis of ATP by ATP synthase . The proton gradient can be generated through either noncyclic or cyclic photophosphorylation . Of the proteins that participate in noncyclic photophosphorylation , photosystem II ( PSII ) , plastiquinone , and cytochrome b f complex directly contribute to generating the proton gradient . For each four photons absorbed by PSII , eight protons are pumped into the lumen . The total equation for photophosphorylation is shown : </P>
<P> Similar to the electron transport chain , the light - dependent reactions of photosynthesis pump protons into the thylakoid lumen of chloroplasts to drive the synthesis of ATP by ATP synthase . The proton gradient can be generated through either noncyclic or cyclic photophosphorylation . Of the proteins that participate in noncyclic photophosphorylation , photosystem II ( PSII ) , plastiquinone , and cytochrome b f complex directly contribute to generating the proton gradient . For each four photons absorbed by PSII , eight protons are pumped into the lumen . The total equation for photophosphorylation is shown : </P>
where does the energy come from to make a proton gradient
where does the energy come from to make a proton gradient
generated through either noncyclic or cyclic photophosphorylation
generated through either noncyclic or cyclic photophosphorylation