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 the permeability of the inner

mitochondrial membrane towards adenosine

diphosphate (ADP)​

Answer 1

The process of oxidative phosphorylation occurs inside mitochondria with the help of electron transporters located in the inner mitochondrial membrane. The flow of electrons in the mitochondrial electron transport system is coupled with the outflow of protons to the peri-mitochondrial space. The accumulation of protons in the peri-mitochondrial space establishes an electrochemical gradient as well as the chemical gradient. The accumulated protons, later on, flow along this electrochemical gradient through F0-f1F0-f1 ATP synthase enzyme complex present on the inner mitochondrial membrane, when ATP is synthesized. This method of ATP synthesis is called as the chemiosmotic mechanism of ATP synthesis.