Glycolysis is anaerobic breakdown of glucose that results in a gain of
two ATP and the end product pyruvate and it takes place in the cytoplasm
of the cell. On the other hand, Krebs cycle is a sequence of enzymatic
reactions involving oxidation of a two-carbon acetyl unit to carbon
dioxide and water to provide energy for storage in the form of high
energy phosphate bonds. The reactions of the Krebs cycle require the
presence of oxygen and are confined to mitochondria.