What is the difference between glycolysis, the krebs cycle, and the electron transport chain?

glycolysis is first step common in both aerobic and anaerobic type of respiration. It occurs in cytosol in this a glucose is converted into 2 molecules of pyruvate. it occurs in absence of oxygen if its anaerobic respiration pyruvate will under go fermentation if its pyruvate molecule will enter in kreb cycle which occurs in mitochondrial matrix. in this NADPH2 FADPH2 is produced. pyruvate molecules formed undergo linker's reaction which connects glycolysis with kreb's cycle and it is converted into acetyl coA with the release of 2 nadh molecules. finally electron transport chain(inner mitochondrial membrane) in which oxygen molecule receives the protons from NADPH2 FADPH2 and generate ATP