Glycolysis takes place in the cytoplasm of cells.
This metabolic pathway is the first step in the breakdown of glucose to extract energy for cellular metabolism. It occurs in the fluid portion of the cell, outside of any organelles. During glycolysis, one molecule of glucose (a 6-carbon sugar) is broken down into two molecules of pyruvate (a 3-carbon molecule). The fate of pyruvate then depends on whether oxygen is present in the cell. If oxygen is present (aerobic conditions), pyruvate enters the mitochondria for further processing in the citric acid cycle and oxidative phosphorylation. If oxygen is absent (anaerobic conditions), pyruvate undergoes fermentation.
In summary, glycolysis doesn't occur within specific organelles, but rather freely in the cytoplasm.
