What does the light dependent reaction of photosynthesis produce?

2 Answers
May 28, 2016



In the non cyclic photophosphorylation light first hits photosystem II where it excites electrons to a higher energy level. The electrons come from the photolysis of a water molecule producing #O_2# and #H^+# in the thylakoid space. The electron moves through some proteins in the electron transport chain which move #H^+# from the stroma to the thylakoid space making a proton gradient.

The electron then moves to photosystem I where it gets excited to a higher energy level again. Then the electron is moved to #NADP^+# reductase, where #NADP^+# are reduced by the electrons.

The proton gradient created between the stroma and thylakoid space cause the #H^+# to flow back into the stroma through proteins in the thylakoid membrane called ATP synthase. The movement of the #H^+# powers the ATP synthase causing the phosphorylation of ADP to ATP.

For more information on the process of photosynthesis, I suggest this animation.

Photosynthesis can broadly be classified into two parts. They are Light Reactions and Dark Reactions.


End products of the Light reaction are ATP, NADPH and Oxygen.
Oxygen escapes into the atmosphere.
ATP & NADPH which is produced is called Assimilatory Power and this will be used in dark reactions of Photosynthesis.