Question

Why should the light – dependent reaction occur before the light-independent reaction?

Answer 1

1. In light – dependent photosynthesis, the photosynthetic pigment absorbs the light energy and convert it into chemical energy, ATP and NADPH₂.
2. These products move out from grana to the stroma of the chloroplast for the light-independent reactions (Dark reaction or Biosynthetic pathway).
3. During this reaction, CO₂ is reduced in the carbohydrates with the help of light generated ATP and NADPH₂.
4. So the light-dependent reaction should occur before the light-independent reaction.