Question

Question 54
What are the important events and end products of the light reaction?

Answer 1

The important events of light reaction are
(i) Excitation of chlorophyll molecule to emit a pair of electrons and use of their energy in the formation of ATP from ADP + Pi. This process is called photophosphorylation.
(ii) Splitting of water molecule
(a) $H_{2}O⟶4H^{+}4e^{-}+O_2\uparrow$ (b) $NADP+2H^{+}⟶NADP{H}_2$
End products of the light reaction are NADPH and ATP.
Reducing power is produced in the light reaction i.e., ATP and $NADP{H}_2$ molecules which are used up in dark reaction, $O_2$ is evolved as a by-product by the splitting of water.