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 Can You Do for Me What Can You Do for Me "What Can You Do For Me" is the debut single by English electronic group Utah Saints. The song was released on 12 August 1991 and reached a peak position of number 10 in the UK Singles Chart. The song uses samples from "There Must Be an Angel (Playing with My Heart)" by Eurythmics and "Ain't Nothin' Goin' on But the Rent" by Gwen Guthrie. The single was released in August 1991 and entered the UK Singles Chart on 18 August at number 26. The song steadily rose up the chart and peaked at number