<P> In the inner mitochondrial membrane, the protein - to - lipid ratio is 80: 20, in contrast to the outer membrane, which is 50: 50 . </P> <P> The inner membrane is freely permeable only to oxygen, carbon dioxide, and water . It is much less permeable to ions and small molecules than the outer membrane, creating compartments by separating the matrix from the cytosolic environment . This compartmentalization is a necessary feature for metabolism . The inner mitochondrial membrane is both an electrical insulator and chemical barrier . Sophisticated ion transporters exist to allow specific molecules to cross this barrier . There are several antiport systems embedded in the inner membrane, allowing exchange of anions between the cytosol and the mitochondrial matrix . </P> <Ul> <Li> Electron transport chain </Li> </Ul> <Li> Electron transport chain </Li>

Mention the use of deep folding in the inner membrane of mitochondria