Photosystem I

-Reaction centre is P700

-It is not associated with splitting of water

-It is found in both - grana and stroma lamellae

-It lies on outer surface of thylakoids

-It participates in both cyclic as well as non cyclic flow of electrons

Photosystem II

-Reaction centre is P680

-It is associated with splitting of water and release of oxygen

-It is found in grana lamellae only

-It lies on inner surface of thylakoids

-It participates only in non cyclic flow of electrons