Anaerobic respiration occurs in the cytoplasm of cells. In anaerobic respiration the six carbon sugar glucose is broken down into two three-carbon molecules called pyruvate. This process converts ADP into ATP, which is the cell's energy storage molecule.
In yeast, anaerobic respiration results in the production of ethanol, which is a type of alchohol. In mammalian muscle tissues, the end result of anaerobic respiration is lactic acid.
By contrast, aerobic respiration, whihc requires oxygen as an electron acceptor, creates much more ATP. Aerobic respiration also begins with glycolysis in the cytoplasm, but continues in the mitochondria.