Chemiosmosis | Cellular Respiration | Class 11 | NBF | FBISE

Chemiosmosis is the process by which cells generate ATP (adenosine triphosphate) during cellular respiration. It occurs in the mitochondria and involves the movement of ions across a selectively permeable membrane, creating an electrochemical gradient. Here's a step-by-step description of chemiosmosis and ATP synthesis: 1. *Electron transport chain*: High-energy electrons from NADH and FADH2 are passed through a series of protein complexes in the mitochondrial inner membrane. 2. *Proton pumping*: As electrons flow through the transport chain, protons (hydrogen ions) are pumped across the membrane, creating a proton gradient. 3. *Electrochemical gradient*: The proton gradient generates an electrochemical gradient, or proton motive force (PMF), across the membrane. 4. *ATP synthase*: The PMF drives the production of ATP through the enzyme ATP synthase, embedded in the mitochondrial membrane. 5. *Proton flow*: Protons flow back across the membrane through ATP synthase, driving the production of ATP from ADP (adenosine diphosphate) and Pi (inorganic phosphate). 6. *ATP synthesis*: The energy from the proton gradient is used to drive the phosphorylation of ADP to ATP, generating a high-energy bond. Chemiosmosis is a critical step in cellular respiration, as it generates the majority of ATP produced during oxidative phosphorylation. This process is essential for energy production in cells, particularly in high-energy demanding tissues like muscle and brain. #federalboard #biology #onlinebiology #humanbody #bioclass #onlinelearning #onlinebiologytutorials #class11 #class12 #electrontransportchain