What is phosphorylation in photosynthesis?
2 Answers
Addition of high energy phosphate to ADP to form ATP is called Phosphorylation. In Photosynthesis it occurs in presence of sunlingt and is called as Photophosphorylation
The phosphorylation ( addition of phosphate ) of ADP to ATP during photosynthesis is called as photophosphorylation.
Explanation:
Light energy trapped during photosynthesis, powers this reaction.
A proton gradient and electrical charge is built up in the thylakoid membranes. This occurs as a result of electron flow during the light reaction , which provides energy to drive the synthesis of ATP from ADP and inorganic phosphorus.
Photophosphorylation occurs in two ways :
1) Noncyclic photophosphorylation
Cytochrome b6f ( enzyme ) uses the energy of electrons from Photosystem (II) to create a proton gradient across the thylakoid membranes. ATP synthatase ( enzyme) uses this energy to form ATP.
2) Cyclic photophosphorylation
In this process cytochrome b6f ( enzyme ) uses energy of electrons from Photosystem (I) and (II) , to create more ATP. It also maintains the right proportion of NADPH for light reaction.
Photosystem (I) and (II) are protein complexes that absorb photons and use their energy.
