Question

multiple choice question
in the light-dependent reactions of photosynthesis, water molecules are split by an enzyme to replace electrons lost by
nadp⁺ in the second electron transport system.
nadph in the second electron transport system.
chlorophyll at photosystem ii.
chlorophyll at photosystem i.

Explanation:

In light - dependent reactions of photosynthesis, at photosystem II, chlorophyll absorbs light energy, which causes it to lose electrons. To replace these lost electrons, water molecules are split by an enzyme (photolysis). NADP⁺ is the final electron acceptor in the electron transport chain and gets reduced to NADPH, not the one that loses electrons to be replaced by water - split electrons. NADPH is the reduced form and doesn't lose electrons in this context to be replaced by water - derived electrons. At photosystem I, the electrons come from the electron transport chain after being passed from photosystem II, not from water splitting. So the correct option is the one about chlorophyll at photosystem II.

Answer:

chlorophyll at photosystem II.