Oxidative phosphorylation

what is a H+ ion also known as?

a proton

which part does chemiosmosis refer to (oxidative phosphorylation and chemiosmosis)?

the part when protons diffuse through channel proteins

what happens during oxidative phosphorylation?

• Reduced NAD is oxidised by NAD dehydrogenase, releasing hydrogen, which separates into H⁺ ions and electrons.

• Electrons pass along electron carriers embedded in the inner mitochondrial membrane, reducing and oxidising each carrier in turn.

• Electrons lose energy as they move along the electron transport chain

what happens during chemiosmosis?

• Energy from electrons pumps H⁺ ions from the mitochondrial matrix into the intermembrane space, creating a proton gradient.

• H⁺ ions diffuse back into the matrix through ATP synthase, providing energy to combine ADP and Pi to form ATP by oxidative phosphorylation.

• Oxygen is the final electron acceptor, combining with electrons and H⁺ ions to form water.

what is the role of reduced FAD in oxidative phosphorylation?

• Reduced FAD is oxidised to FAD, releasing electrons into the electron transport chain further along than reduced NAD

• Its electrons release less energy, so fewer H⁺ ions are pumped into the intermembrane space and less ATP is produced

• H⁺ ions released from reduced FAD remain in the matrix and can combine with oxygen and electrons to form water