<prompt> Protein to lipid ratio is LEAST in:Inner mitochondrial membraneOuter mitochondrial membraneRBC membraneMyelin sheath  <response>: Myelin sheath has the least Protein:Lipid Ratio Membrane Protein Lipid Carbohydrate Red blood cell membrane 49 43 8 Myelin around nerve cells 18 79 3 Inner mitochondrial membrane 76 24 0 