The processes that use the mechanisms are: Cellular respiration â ATP is generated by oxidation of organic molecules, the passage of electrons down an electron transport chain, and chemiosmosis. The final electron acceptor is almost always inorganic. Aerobic â the final electron acceptor is O 2.
The Sumerians lived in Mesopotamia around 4000 BC. Mesopotamia or the Fertile Crescent was a region in the Middle East between the Tigris and Euphrates rivers, in the territory of modern Iraq, Iran and Syria.
A brief treatment of Sumerian civilization follows. For full treatment, see Mesopotamia, history of: Sumerian civilization. Sumer was first settled between 4500 and 4000 bce by a non-Semitic people who did not speak the Sumerian language. These people now are called proto-Euphrateans or Ubaidians, for the village Al-Ubaid, where their remains were first discovered.