Question

Which one is involved in $Z$-scheme of photosynthesis?

• A. $ PS I $
• B. $PS II $
• C. $e^{-}$ carriers
• D. All of these

Answer 1

The Correct Option is D

In non cyclic photophosphorylation, the whole scheme of transfer of electrons, starting from the $PS II$, uphill to the acceptor, down the electron transport chain to $PS I$, excitation of electrons, transfer to another acceptor, and finally down hill to $NADP^{+}$ causing it to be reduced to $NADPH + H^{+}$ is called as the $Z$ scheme, due to its characteristic shape. This shape is formed when all the carriers are placed in a sequence on the redox potential scale.

Answer 2

Ans: During the Z scheme of photosynthesis, all three that are PS I, PS II and electron carriers are involved. Zsheme is a light dependent reaction of photosynthesis. The scheme represents the flow of electrons from a zig zag pattern that is formed due to the movement of electrons. During a Z scheme:

Photosystem II: PS II is the first photosystem unlike the name. It will capture the light energy and will energise the electrons. Water molecules are also spilt to release oxygen, protons and electrons. These electrons will then be passed to the chain.

Electron carrier: there are a series of electrons carriers that are involved in this process. They are present in the thylakoid membrane and the chloroplast. 

These carriers will transfer the electron from PSII to PSI. 

PSI: Another photosystem in the Z scheme is PSI, it will capture the light energy and re-energize the  electrons. Here the reduction of NADP+ to NADPH occurs.