What is the relationship between the etc and oxygen?

The electron transport chain (ETC) is a series of protein complexes located in the inner mitochondrial membrane that plays a crucial role in cellular respiration. Oxygen serves as the final electron acceptor in the ETC, allowing the chain to continue functioning. When electrons are transferred through the chain, they ultimately combine with oxygen and protons to form water, a process that also helps generate a proton gradient used to produce ATP. Without oxygen, the ETC would become backed up, halting ATP production and leading to cellular energy deficiency.