The primary immune response is the production of antibodies and memory cells. B plasma cells can make about 2000 antibodies every second and only last a few days. The antibodies help to destroy the pathogen.The secondary immune response occurs at a later date if the memory cells encounter the same antigen. They then develop rapidly into B plasma cells and B memory cells. The plasma cells produce antibodies that destroy the pathogen. The new memory cells circulate around the body ready for any future exposure to the antigen by infection. Memory cells ensure that an increased quantity of antibodies is produced at a faster rate upon subsequent infection by the same pathogen.