Question

Which is not an electron carrier?

• A. CoQ
• B. Cyt c
• C. Cyt a
• D. $H_{2}O$

Answer 1

The correct option is D $H_{2}O$

In an electron transport process, the excited electron from PS II is accepted by primary acceptor quinone, which sends them to an electron transport system consisting of plastoquinone, cytochrome complex and plastocyanin. The excited electron absorbed by PS I reaction centre, then transfer to the ferredoxin (Fe), then the reduced Ferredoxin donates the electron to NADP${}^{+}$. H${}_2$O undergoes photo-oxidation or photolysis to provide the electrons to the PS II and to release the oxygen.

Hence, the correct answer is 'H${}_2$O'.