The series of protein complexes and organic molecules embedded in the inner mitochondrial membrane (in eukaryotes) or the plasma membrane (in prokaryotes) facilitates a crucial process. These entities accept and donate electrons in a sequential manner, ultimately leading to the generation of a proton gradient. Cytochromes, quinones, and iron-sulfur proteins are essential participants in this electron relay system.
This system is fundamental to cellular respiration, enabling the efficient extraction of energy from nutrient molecules. The proton gradient generated is then used to power ATP synthase, producing the majority of ATP required by the cell for various energy-demanding processes. Its discovery and understanding have been instrumental in advancing knowledge of bioenergetics and cellular metabolism.
