QUESTION 1 Describe in detail the route of electron flow fro

QUESTION 1

Describe in detail the route of electron flow from NADH to oxygen that establishes a proton gradient across the inner mitochondrial membrane.

QUESTION 2

When the F₁ portion of the ATP synthase complex is removed from the mitochondrial membrane and studied in solution, it functions as an ATPase. Why does it not function as an ATP synthase?

Solution

NADH is rich source of electrons and possess high Reduction potential which is produced from Glycolysis and Krebs cycle. It readily transfer electrons to complex-1 of Electron transport Chain located in Inner mitochondrial membrane. Then the electrons move to Ubiquinone, Complex-3, Cytochrome-C, Complex-4 and finally to Oxygen. All these moment of electrons occur passively, so free energy is released. The released free energy pumps the electrons from mitochondrial matrix to perimitochondrial space (Space between mitochondrial inner and outer membrane). This occur as follows: Through Complex-1: 4 electrons, Complex-3: 4 electrons and Complex-4: 2 electrons pumped to perimitochondrial space. So every 2electrons transfer from NADH to Oxygen, total 10 protons pumped from matrix to Perimitochondrial space and gives 2.5 ATP

The F1 portion of the ATP synthase is essential for the integration of H+ ion motive force, to combine ADP and Pi to give ATP. If this F1 portion removed, it cannot integrate the H+ motive force and ATP formation.