B cell
A type of white blood cell and, specifically, a type of lymphocyte.
Many B cells mature into what are called plasma cells that produce antibodies (proteins) necessary to fight off infections while other B cells mature into memory B cells.
All of the plasma cells descended from a single B cell produce the same antibody which is directed against the antigen that stimulated it to mature.
The same principle holds with memory B cells.
Thus, all of the plasma cells and memory cells 'remember' the stimulus that led to their formation.
</P> The maturation of B cells takes place in birds in an organ called the bursa of Fabricus.
B cells in mammals mature largely in the bone marrow.
The B cell, or B lymphocyte, is thus an immunologically important cell.
It is not thymus-dependent, has a short lifespan, and is responsible for the production of immunoglobulins.
It expresses immunoglobulins on its surface.