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) peaking at #1 on the "Billboard" R&B singles chart in 1990. 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