Study the following statements and find which are correct and which are incorrect with respect to photosynthetic electron transport?

A. The electrons removed from PSI are compensated by getting electrons from PSII.

B. The electrons removed from PSII is compensated by getting electrons from water. 

C. The electrons removed from PSI always reach the NADP to form reducing power.

D. During non-cyclic electron transport, there is cyclic electron transport in which Cytochrome ${\mathrm{b}}_6$ and PQ are involved.

Solution:

During non-cyclic electron transport of photosynthesis, the electrons removed from PSI by NADP is compensated by getting electrons from PSII. The electrons removed from PSII is compensated by getting electrons from Water via oxygen evolving complex. During non-cyclic electron transport there is cyclic electron transport during the operation of PQ cycle which helps in pumping additional protons from stroma to lumen to establish proton gradient for the formation of ATP. During non-cyclic electron transport only the electrons removed from PSI are accepted by NADP where as in cyclic electron transport the electrons reach the same PSI (P700) but do not reach the NADP.