Final answer:
A mature B cell predominantly produces more IgM than IgD on the cell surface, as IgM is the main antibody secreted by plasma cells during immune responses, while IgD is found in only trace amounts.
Step-by-step explanation:
The question concerns whether a mature B cell produces more IgM or IgD on the cell surface. IgM is the predominant immunoglobulin expressed on the surface of naïve B cells along with IgD. During B cell maturation, the IgM receptors bind to antigens, and following activation, the B cell undergoes clonal proliferation.
The daughter cells differentiate into plasma cells, which then secrete large quantities of antibodies, predominantly pentameric IgM, specific to the recognized antigen. IgM, first secreted during the primary and secondary immune responses, is a crucial antibody in the defense against pathogens.
In contrast, IgD is found in only trace amounts in serum and on the surface of B cells, serving more in the role of antigen recognition than in the abundant secretion of antibodies.