Photosynthetic pigment at 400-530 nm. However, none of the pigments absorbs well in the green-yellow region, which is responsible for the abundant green we see in nature. Like plants, the cyanobacteria use water as an electron donor for photosynthesis and therefore liberate oxygen; they also use chlorophyll as a pigment. In addition, most cyanobacteria use phycobiliproteins, water-soluble pigments which occur in the cytoplasm of the chloroplast, to capture light energy and pass it on to the chlorophylls. (Some cyanobacteria, the prochlorophytes, use chlorophyll b instead of phycobilin.) It is thought that the chloroplasts in plants and algae all evolved from cyanobacteria. Several
Photon energy to date, very-high-energy gamma rays, have photon energies of 100 GeV to 100 TeV (10 to 10 electronvolts) or 0.016 microjoules to 0.016 millijoules. This corresponds to frequencies of 2.42 × 10 to 2.42 × 10 Hz. A photon with a wavelength equal to the Planck length would have an energy of about 7.671 × 10 eV or 1.229 × 10 joules (12.29 gigajoules). This is roughly the amount of energy produced by the world's most powerful coal-fired power station, the Taichung Power Plant, during a period of 2.25 seconds. During photosynthesis, specific chlorophyll molecules absorb red-light photons at a