Why is photolysis of water accompanied with non-cyclic photophosphorylation?

1. Photolysis of water provides new electrons to Photosystem – II. 

2. The water molecule is lysed into three components: 

a. Protons (H+) which are used as part of reactions that makes NADPH. 

b. Second component formed is electrons which replaces the electrons lost by PS-II. 

c. The third component is oxygen (O₂) which is released into the atmosphere. 

3. Photosystem I sends electrons to reduce NADP⁺. 

4. Then, Photosystem II sends replacement electrons to Photosystem I. 

5. Finally, photolysis of water replaces the electrons lost by Photosystem II. 

6. Water is the ultimate source of electrons for photosynthesis. Therefore, photolysis of water is accompanied with non – cyclic photophosphorylation.