Answer:
Mobile
Step-by-step explanation:
Plastoquinone has a similar structure and role to Ubiquinone, found in other electron transport chains. It's a mobile electron transport carrier through the thylakoid membrane (thylakoids are present in chloroplasts), and is present in the photosystem II in plants and other photosynthetic organisms. PSII produces the chemical energy as ATP.
PQ is reduced when it accepts electrons from PSII, and then it delivers them to plastocyanin, that is a water-soluble electron carrier in the cytochrome b6f complex.