What are the light and dark phases of photosynthesis?

Question

please explain!

Answer 1

The light reactions of photosynthesis require light.  These processes extract electrons from water and use light energy to produce high energy substrates NADPH and ATP.  This is perform by a long sequence of electron transfers associated with the membrane system of the chloroplast.

The dark reaction of photosynthesis occur in the soluble matrix outside of the membrane system described above.  The dark reactions are called such since they do NOT require light.  Instead, they use the light-generated substrates NADPH and ATP to convert CO2 to carbohydrate in a cycle of organic interconversions called the Calvin cycle.  Thus, the light and dark reactions certainly interact but involve quite distinct subsets of proteins and cofactors in the chloroplast.  They are also distinct in their locations.