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.
The early Sumerian cities were characterized by a high degree of social and economic diversity, which gave rise to artisans, merchants, priests, bureaucrats, and for the first time in history, professional soldiers.