Photosynthesis More recent studies, reported in March 2018, also suggest that photosynthesis may have begun about 3.4 billion years ago. The main source of oxygen in the Earth's atmosphere derives from oxygenic photosynthesis, and its first appearance is sometimes referred to as the oxygen catastrophe. Geological evidence suggests that oxygenic photosynthesis, such as that in cyanobacteria, became important during the Paleoproterozoic era around 2 billion years ago. Modern photosynthesis in plants and most photosynthetic prokaryotes is oxygenic. Oxygenic photosynthesis uses water as an electron donor, which is oxidized to molecular oxygen () in the photosynthetic reaction center. Several groups of animals
What I Need has done wrong. Despite its sap factor, "What I Need" will likely lap up radio play." The remix version with West Coast rappers Nate Dogg, Shorty Mack, Slim Thug and Snoop Dogg became even more popular being watched more than 200,000 times on YouTube. It's called "Smokin Trees (What I Need Remix)" and produced by Ray J for Knockout Entertainment and was expected to be released as "Smokin Smokin Weed" which featured Ray J, Nate Dogg and Snoop Dogg only, on "Tha Blue Carpet Treatment" by Snoop Dogg. What I Need "What I Need" is a song by American recording