Question

The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that Adenosine Triphosphate (ATP) is formed because

• A. High energy bonds are formed in mitochondrial proteins
• B. ADP is pumped out of the matrix into the intermembrane space
• C. A proton gradient forms across the inner membrane
• D. There is a change in t of the permeability inner mitochondrial membrane toward Adenosine Diphosphate (ADP)

Answer 1

Answer: (C)

The production of ATP with the help of energy liberated during oxidation of reduced coenzymes and terminal oxidation is called oxidative phosphorylation. Peter Mitchell (1961) put forward a hypothesis known as chemiosmotic hypothesis for ATP synthesis. According to this when electrons flow from duel proton, electron carrier to a non-hydrogen carrier the H⁺ are released and expelled into the intermembrane space and thus creates a proton gradient with higher concentration of H⁺ in the inter membranous space than the matrix. Due to proton motive force the protons flow back and energy liberated during this back flow of protons activate ATPase [present in F₁ head to synthesize ATP].