elektrontranszporthoz

Elektrontranszporthoz, commonly referred to as the electron transport chain (ETC), is a crucial biological process occurring in the mitochondria of eukaryotic cells and the plasma membrane of prokaryotic cells. It is the final stage of cellular respiration, where the majority of ATP, the cell's energy currency, is produced. The ETC is a series of protein complexes and electron carrier molecules embedded within a membrane.

Electrons, carried by molecules like NADH and FADH2, are donated to the first complex in the chain. As these electrons move from one complex to the next, they release energy. This released energy is used by some of the protein complexes to pump protons (H+ ions) across the membrane, creating an electrochemical gradient. This gradient represents a form of potential energy.

The flow of electrons continues through the chain, with oxygen acting as the final electron acceptor, forming water. The accumulated protons then flow back across the membrane through a specialized enzyme called ATP synthase. This movement of protons through ATP synthase drives the synthesis of ATP from ADP and inorganic phosphate, a process known as chemiosmosis. The efficiency of ATP production through oxidative phosphorylation, which includes the electron transport chain and chemiosmosis, is significantly higher than that of anaerobic respiration. This process is fundamental for supplying the energy required for most cellular activities.