What is the e donor in the photosynthesis system And is this

What is the e- donor in the photosynthesis system? And is this e- transfer perfect and why?

photolysis of water (an electron donor) produces oxygen molecules SO HERE WATER IS HYDROGEN DONOAR IN PHOTOSYNTHESIS

this is perfect reaction because in photolysis during photosynthesis two water molecules are oxidized through four successive charge-separation reactions to yield a molecule of diatomic oxygen and four hydrogen ions