<prompt> Pentavalent immunoglobin is-IgAIgGIgMIgE  <response>: IgM IgM is Pentavalent Ig It has max molecular weight It has max sedimentation coefficient IgM is produced first in immune response IgM plays a role in :- 1. Opsonisation 2. Classical complement pathway 3. IgM IgD are present over B cell surface 