The electron transport chain takes place in the membranes of the mitochondria in eukaryotic cells. Electron transport is the last stage of cell respiration. The chain passes high-energy electrons formed during glycolysis into oxygen-creating adenosine triphosphate (ATP) for energy.
Cellular respiration is the process through which cells convert glucose into ATP for energy. The first phase, glycolysis, starts breaking down the glucose in the cell's cytoplasm. The second phase, the citric acid cycle, creates high-energy electrons by passing the broken-down glucose through several chemical reactions. The third phase, electron transport, moves the high-energy electrons through a chain of redox reactions in the mitochondrial membrane to create ATP.