Difference Between Cyclic and Non Cyclic Photophosphorylation

Photosynthesis is the process of producing carbohydrates by green plants using CO2 and H2O in the presence of sunlight.

It is a two-step process light reaction and dark reaction

• Light reaction takes place in the grana of the chloroplast where light energy is converted to chemical energy as ATP and NADPH
• In dark reaction, the energy produced in the light reaction is utilized to fix CO2 to carbohydrates. The location of dark reaction is stroma of the chloroplast

Cyclic photophosphorylation vs Non Cyclic photophosphorylation

Photophosphorylation
In light reaction, addition of phosphate in the presence of light is called photophosphorylation.

Cyclic photophosphorylation The photophosphorylation occurring an cyclic electron transport called cyclic photophosphorylation

1. Only photosystem I is involved

2. The active reaction centre is P700

3. Electrons travels in a cyclic manner

4. Electron travels back to PS I

5. Only ATP is produced

6. Photolysis or water splitting is absent

7. Oxygen is not evolved

8. The system is predominant in bacteria

Non-Cyclic photophosphorylation The photophosphorylation occurring a non-cyclic electron transport is called non cyclic photophosphorylation.

1. Both photosystem I and II are involved

2. The active reaction centre is P680

3. Electrons travels in a non-cyclic manner

4. Electron from PS I is accepted by NADP

5. Both ATP and NADPH are produced

6. Photolysis or water splitting is present

7. Oxygen is evolved as a by-product

8. The system is predominant in green plants