Under which conditions cyclic photophosphorylation will take place?
- Cyclic photophosphorylation take place under conditions which exclude non-cyclic photophosphorylation
- The situation is created if the activity of pigment system II blocked .This will be accomplished by the use of specific inhibitors or by using wavelength of light greater than 680mu.
- Under this conditions
- only pigment system- I remains active
- photolysis of water does not take place.
- blockage of non-cyclic ATP formation causes a drop in CO2 assimilation in dark reaction.
- and there is a consequent shortage of oxidised NADP+
- When P700 molecules is active
- The expelled electron returns to the same chlorophyll after loosing its excess energy in the synthesis of ATP
- NADPH2 not produced in cyclic photophosphorylation
- Photolysis of water not takes place
- This is happened when there is more demand for ATP production or it may be due to the non-availability of NDPH+ for reduction