Photosynthesis called P680. The source of electrons for photosynthesis in green plants and cyanobacteria is water. Two water molecules are oxidized by four successive charge-separation reactions by photosystem II to yield a molecule of diatomic oxygen and four hydrogen ions. The electrons yielded are transferred to a redox-active tyrosine residue that then reduces the oxidized P680. This resets the ability of P680 to absorb another photon and release another photo-dissociated electron. The oxidation of water is catalyzed in photosystem II by a redox-active structure that contains four manganese ions and a calcium ion; this oxygen-evolving complex binds two water molecules and
What You Need (Stacy Lattisaw album) What You Need (Stacy Lattisaw album) What You Need is the tenth and final studio album by American contemporary R&B singer Stacy Lattisaw, released October 17, 1989 via Motown Records. It did not chart on the "Billboard" 200, but it peaked at #16 on the "Billboard" R&B chart. It was also Lattisaw's final album before she retired from the music industry. Four singles were released from the album: "What You Need", "Where Do We Go from Here", "Dance for You" and "I Don't Have the Heart". "Where Do We Go from Here" was the most successful single from the album,