The movement of electrons down the ETC drives the formation of a proton gradient.
Step-by-step explanation:
ETC or electron transport chain transfers electron from the donors of electron to the acceptors through the process of redox. This transfer is later coupled with proton transfer throughout the membrane. However, this transfer drives the gradient of proton formation through the ATP synthesis.
The chain includes molecules of enzymes. This chain finally accepts the oxygen molecules by the respiration process in plants. An important ETC is located at the membrane of mitochondria in eukaryotes.