Chlorophyll a Chlorophyll a Chlorophyll "a" is a specific form of chlorophyll used in oxygenic photosynthesis. It absorbs most energy from wavelengths of violet-blue and orange-red light. It also reflects green-yellow light, and as such contributes to the observed green color of most plants. This photosynthetic pigment is essential for photosynthesis in eukaryotes, cyanobacteria and prochlorophytes because of its role as primary electron donor in the electron transport chain. Chlorophyll "a" also transfers resonance energy in the antenna complex, ending in the reaction center where specific chlorophylls P680 and P700 are located. Chlorophyll "a" is essential for most photosynthetic organisms to release
Light-dependent reactions poorly understood structure embedded within PS II called the "water-splitting complex" or the "oxygen-evolving complex". It catalyzes a reaction that splits water into electrons, protons and oxygen: 2 → 4H + 4e + The actual steps of the above reaction are running in the following way (Dolai's diagram of S-states): The electrons are transferred to special chlorophyll molecules (embedded in PS II) that are promoted to a higher-energy state by the energy of photons. The excitation P680 → P680of the reaction center pigment P680 occurs here. These special chlorophyll molecules embedded in PS II absorb the energy of photons, with