Question

Find out the correct combination concerning the components of photosynthetic electron transport, location in relation to thylakoid and action.
(I) OEC - lumen side - water reduction
(II) Plastocyanin - lumen side - electron transfer from cytochrome f to PS I
(III) Ferredoxin - stroma side - reduction of NAD${}^{+}$ to NADH
(IV) Cytochrome complex - integral protein - transfer electrons from $PQ{H}_2$ to $PC$
The correct answer is

• A. (II), (IV)
• B. (I), (III)
• C. (II), (III)
• D. (I), (IV)

Answer 1

Answer: (A)

(II), (IV)

Plastocyanin is a copper-containing protein that plays a role in the electron transport process associated with photosynthesis. It serves as an electron transfer agent between the cytochrome complex which follows Photosystem II and the entry point to Photosystem I of the non-cyclic electron transfer process.
The cytochrome b6f complex (plastoquinol—plastocyanin reductase) is an enzyme found in the thylakoid membrane in chloroplasts of plants, cyanobacteria, and green algae, that catalyze the transfer of electrons from plastoquinol to plastocyanin.