The electron transport chain (ETC) is the ultimate stage of mobile respiration, occurring throughout the mitochondria. It includes a sequence of protein complexes that facilitate the switch of electrons from NADH and FADH2 to molecular oxygen. This electron switch releases power, which is then used to pump protons (H+) throughout the inside mitochondrial membrane, creating an electrochemical gradient. This gradient, often known as the proton-motive drive, is a type of potential power.
The power saved within the proton-motive drive is harnessed by ATP synthase, an enzyme that enables protons to move again throughout the membrane down their electrochemical gradient. As protons move by way of ATP synthase, the enzyme rotates, catalyzing the phosphorylation of ADP to ATP. This course of is named oxidative phosphorylation and is the first mechanism by which cells generate the vast majority of their ATP. Understanding the effectivity of this course of is essential for comprehending mobile power budgets and metabolic regulation. Traditionally, estimations diversified, however present analysis supplies extra refined values.