photosystem - PS1 ,PS2
Photosystem I and II are protein complexes present in the thylakoid membrane of chloroplast. Their role is to transfer electrons to the NADP and ADP. These are surrounded by the light harvesting complexes to harvest photons of light and they also have reaction centers to emit and transfer the electrons.
Photosystem II has P680 reaction center and Photosystem I has P700 reaction center.
After harvesting the photon of light P680 emit an electron that is transferred to the P700 and it further transfer the electron to the NADP and ADP to form NADPH and ATP.