Ferredoxin is a

Provide definitions/explanations for the following terms:
$(1)$ Photosynthesis
$(2)$ Light reaction

$PS-I$ in cyclic photophosphorylation is involved in the formation of ...$A$... by ...$B$... movement of electrons. What do $A$ and $B$ refer to here?

Electric charge separation or quantum conversion occurs at

Photophosphorylation is the synthesis of ..........

What is required for the photolysis of water?