Q.B Cells that produce and release large amounts of antibody is called :

Plasma cells are antibody 'factories' -- the effector form that activated B cells become.

When a B lymphocyte encounters its specific antigen (often with helper T-cell assistance), it proliferates and differentiates mainly into plasma cells, which are packed with extensive rough endoplasmic reticulum specialised for synthesising and secreting large quantities of antibody (immunoglobulin) molecules matching that antigen. Killer (cytotoxic T) cells directly destroy infected/abnormal cells rather than secreting antibody; memory cells persist long-term to enable a faster response on re-exposure but do not thems …