Answer:
Stage 1 is Catabolism: The carbohydrates, proteins, and lipids get dissociated into their individual monomeric units, that is, fatty acids, simple sugars, and amino acids respectively.
Stage 2 is Metabolic pathways (Beta-oxidation and glycolysis); In the stage, the monomeric units further get dissociated by specific metabolic pathways to produce a common end component, that is, Acetyl-CoA.
Stage 3 is the Krebs cycle: Acetyl-CoA gets completely oxidized to produce water, carbon dioxide, and reducing units like NADH, FADH2 and GTP.
Stage 4 is Electron transport system or chain: In the process, production of ATP takes place by proton motive force, energy is created by the gradient, that is, produced when the protons move across the biological membrane.