Electron transport is a process that occurs in the mitochondria of cells, where electrons are transferred through a series of proteins known as the electron transport chain. This chain is essential for producing energy in the form of ATP (adenosine triphosphate), which cells use to perform various functions. During electron transport, electrons derived from NADH and FADH2 are passed along the chain, releasing energy. This energy is used to pump protons across the mitochondrial membrane, creating a gradient. When protons flow back through the enzyme ATP synthase, ATP is generated, completing the energy production process.