Light-Dependent Reactions
The Light-Dependent Reactions occur in the Thylakoid membranes and require light to produce ATP and NADPH.
When photons strike Chlorophyll molecules in Photosystem II, electrons are excited and passed through the Electron Transport Chain, generating a Proton Gradient.
This gradient powers ATP Synthase to produce ATP. Electrons are then passed to Photosystem I, where they are re-energized and used to reduce NADP+ into NADPH.
The splitting of water, or Photolysis, replenishes lost electrons in Photosystem II and releases Oxygen as a Byproduct.