<prompt> Poion of immunoglobulin molecule with molecular weight of 50,000-Secretory pieceH chainL chainj piece  <response>: Antibody or immunoglobulin are glycoproteins molecules consisting of four polypeptide chains. - two identical heavy chains H , molecular weight 50 kDa. Two identical light chains L, molecular weight 25kDa. Reference : Anathanarayan panikers 9th edition, pg no: 94 p 