How does the reaction center pigment differ from antenna pigments in photosynthesis?

• A. It loses an electron when it absorbs light energy.
• B. It stores light energy as chemical energy directly.
• C. It transfers energy directly to NADP+.
• D. It splits water to release oxygen.

Answer: (A)

In photosynthesis, antenna pigments only capture light and funnel that energy to the reaction center. The reaction center, upon absorbing a photon, undergoes charge separation by transferring an electron to the primary electron acceptor, which oxidizes the reaction center. This is the direct step that converts light energy into chemical energy and starts the electron transport chain.

So the key idea is that the reaction center pigment loses an electron when it is excited, initiating electron transfer. Antenna pigments don’t undergo this redox change—they only pass along the energy. The other options aren’t correct because energy isn’t stored directly as chemical energy by the reaction center, NADP+ is reduced later downstream in the chain, and water splitting is carried out by the oxygen-evolving complex associated with photosystem II, not by the reaction center pigment itself.