<prompt> Which is not a RBC membrane protein?AnkyrinNebulinSpectrinGycophorin  <response>: The protein skeleton consists of 2D mesh of spectrin tetramers and oligomers. It is attached to RBC membrane by attaching to ankyrin. Membrane proteins like glycophorin also present. Ref: Textbook of medical physiology by N Geetha, 3rd edition, page no. 77 