Occurring in the membrane, H+ are transported across the membrane into/out of the matrix. Chemiosmosis involves the establishment of a proton gradient across a membrane- used to drive ATP Synthesis. Energy from the electrons is used to transport H+.

Chemiosmosis is when ions move by diffusion across a semi-permeable membrane, such as the membrane inside mitochondria. Ions are molecules with a net electric charge, such as Na+, Cl–, or specifically in chemiosmosis that generates energy, H+. Ions also move to balance out the electric charge across a membrane.

1: Chemiosmosis: In oxidative phosphorylation, the hydrogen ion gradient formed by the electron transport chain is used by ATP synthase to form ATP. The turning of this molecular machine harnesses the potential energy stored in the hydrogen ion gradient to add a phosphate to ADP, forming ATP.

In biology, chemiosmosis refers to the process of moving ions (e.g. protons) to the other side of the membrane resulting in the generation of an electrochemical gradient that can be used to drive ATP synthesis. The differences in the pressures between the two sides of the membrane drive osmosis.

The process of chemiosmosis dries ATP synthesis using the potential energy of a concentration gradient of hydrogen ions (H+) across a membrane. The gradient is created when an electron transport chain uses the energy released as it passes electronsdown the chain to pump hydrogen ions across a membrane.

Most biochemists agree that 36 molecules of ATP can be produced for each glucose molecule during cellular respiration as a result of the Krebs cycle reactions, the electron transport system, and chemiosmosis. Also, two ATP molecules are produced through glycolysis, so the net yield is 38 molecules of ATP.

This process is related to osmosis, the diffusion of water across a membrane, which is why it is called “chemiosmosis”. It allows protons to pass through the membrane and uses the free energy difference to phosphorylate adenosine diphosphate (ADP), making ATP.

Chemiosmosis is the method which cells use to create ATP for energy. It works a bit like a water wheel creating power. ATP synthase is like a water wheel in the inner membrane of mitochondria which creates ATP by forcing ADP and phosphate together.

During chemiosmosis, the free energy from the series of reactions that make up the electron transport chain is used to pump hydrogen ions across the membrane, establishing an electrochemical gradient. The production of ATP using the process of chemiosmosis in mitochondria is called oxidative phosphorylation.

Krebs cycle

When glucose is used as an energy source, the largest amount of ATP is generated by the electron transport chain portion of the entire respiratory process. Glycolysis generates approximately 2 net ATP.

Krebs Cycle Produces most of the ATP in cellular respiration.