In many bacteria, specially the Gram positive bacteria, the plasma membrane gives rise to infoldings called mesosomes. These are finger like spherical or villiform structures which may help compartamentalize the cell. The surface of mesosomes has many respiratory enzymes which take part in respiration. Although mesosomes participate in aerobic respiration of bacteria but the whole plasmalemma takes part in this process. They also assist in cell wall formation and coordinate nuclear and cytoplasmic division during binary fission.