Answer:
C) thylakoid; light-dependent
Step-by-step explanation:
Photosystems are photochemical complexes known as photosystems I and II (PSI and PSII), which despite their spatial separation work in series, through electron transport, to perform the energy storage reactions of photosynthesis. Both can be found in the tilacoid membrane and participate in the clear phase of photosynthesis, that is, they participate in light-dependent reactions.
In photosystem I, chlorophyll a predominates, while in photosystem II, chlorophyll b predominates.
Chlorophyll a, illuminated by sunlight, loses a pair of activated electrons, collected by a special acceptor, ferridoxine. At the same time, chlorophyll b, excited by sunlight, loses a pair of electrons that, after crossing a chain of cytochromes, occupy the "void" left in the chlorophyll a molecule. During the passage of these electrons through the cytochrome chain, there is energy release and ATP (phosphorylation) production. Since the "electron void" of chlorophyll a is not filled by the same electrons that came out of this molecule, the mechanism is called acyclic photophosphorylation.