How do plants make ATP?

1 Answer
Oct 16, 2017

Photosystem II


During photosynthesis, plants use sunlight to energize the decomposition of water into hydrogen ions and free oxygen gas (which is eliminated as waste byproduct). The energy of the electron is exchanged through a series of proteins in the thylakoid membrane to pump ions into the lumen of the thylakoid.

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These hydrogen ions build up osmotic potential across the thylakoid membrane of the granum within chloroplasts - an enzyme called ATP Synthase (yes, the very same as respiration) allows the hydrogen ions to move from the lumen back into the stroma across the thylakoid membrane, alleviating the stress of the concentration difference & manufacturing ATP in the coupled process.