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 Do I Do with Me covered by Reba McEntire for her 1994 album, "Read My Mind." As listed in liner notes. What Do I Do with Me What Do I Do with Me is a 1991 album by American country music singer Tanya Tucker. It was her highest-placing on the Billboard charts reaching #6 in the Country albums and #48 on the Pop albums categories. The album produced four Top Ten hits on the Hot Country Songs charts: "(Without You) What Do I Do with Me" and "Down to My Last Teardrop" both at number two, "Some Kind of Trouble" at number three, and "If