Explain photophosphorilation

The process of generating ATP from ADP by addition of one phosphate group in presence of light energy is called photophosphorylation. Photophosphorylation is carried out by means of a proton-motive force generated by the thylakoid membrane of the chloroplast.  In light reaction, there are 2 pathways of photophosphorylation i.e. cyclic and non-cyclic.

During cyclic process, the high energy rich electron emitted from chlorophyll-a returns to chlorophyll-a, hence the name. Here only ATP is produced.

But in non-cyclic photophosphorylation, the high energy rich electron emitted by chlorophyll-a does not return to chlorophyll-a. Here both ATP and NADPH₂ are produced.