(N/A) Oxidative phosphorylation is a process in which electrons are transferred from electron donors to oxygen,which acts as the final electron acceptor.
This process involves oxidation-reduction reactions that lead to the formation of a proton gradient across the inner mitochondrial membrane.
The main role in oxidative phosphorylation is played by the enzyme $ATP$ synthase (complex $V$).
This enzyme complex consists of $F_{0}$ and $F_{1}$ components.
The $F_{1}$ headpiece is a peripheral membrane protein complex and contains the site for $ATP$ synthesis from $ADP$ and inorganic phosphate.
The $F_{0}$ component is an integral membrane protein complex that acts as a channel for the movement of protons from the intermembrane space to the mitochondrial matrix.
For every two protons passing through the $F_{0}-F_{1}$ complex,the synthesis of one $ATP$ molecule takes place.