Rafeinaflutningskeðjunni

Rafeinaflutningskeðjunni is a term of Icelandic origin that translates to "electron transport chain" in English. This is a fundamental biological process that occurs within the mitochondria of eukaryotic cells and in the cell membranes of prokaryotic organisms. The electron transport chain is the final stage of cellular respiration, where the majority of ATP, the primary energy currency of the cell, is produced.

The process involves a series of protein complexes embedded in a membrane. These complexes accept electrons from electron carriers, such as NADH and FADH2, which were generated during earlier stages of respiration like glycolysis and the Krebs cycle. As electrons are passed from one complex to the next, they release energy. This energy is used to pump protons (H+) across the membrane, creating an electrochemical gradient.

This proton gradient represents potential energy. Protons then flow back across the membrane through a specialized enzyme called ATP synthase. This flow of protons drives the synthesis of ATP from ADP and inorganic phosphate. Oxygen acts as the final electron acceptor in the chain, combining with electrons and protons to form water. The efficiency and importance of the electron transport chain for sustaining life are immense, as it generates the bulk of the energy required for cellular functions.