Question

Last electron acceptor of PS I is

• A. Ferredoxin
• B. Cyt $b_6$
• C. Plastocyanin
• D. Plastoquinone

Answer 1

The correct option is A Ferredoxin

In the electron transport process, the excited electron from P${}_{680}$ 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 P${}_{700}$ reaction centre, then transfer to the ferredoxin (Fe), then the reduced Ferredoxin donates the electron to NADP${}^{+}$.

The NADP${}^{+}$ take an electron from ferredoxin, protons from the medium and get reduced to NADPH in presence of enzyme ferredoxin- NADP- reductase. So, the last electron acceptor of PS I is ferredoxin.

Hence, the correct answer is 'Ferredoxin'.