1. Light Absorption:
* PSII absorbs light energy, which excites electrons within its reaction center chlorophyll molecules.
2. Water Splitting:
* This excitation energy is used to split water molecules (H₂O) into their components:
* Electrons: These electrons replace the excited electrons that were ejected from the PSII reaction center.
* Protons (H+): These protons are released into the thylakoid lumen (the space inside the thylakoid membrane).
* Oxygen (O2): This is released as a byproduct of the water splitting process.
3. Electron Transport Chain:
* The electrons extracted from water are passed through an electron transport chain, ultimately leading to the production of ATP (energy currency of the cell).
In summary: Photosystem II enzyme uses light energy to split water molecules, releasing electrons, protons, and oxygen. The released electrons are then used to power the electron transport chain, while the protons contribute to the creation of a proton gradient that drives ATP production.
