Outline the process of the primary immune response to a pathogen.

The pathogen is first phagocytosed or engulfed by a phagocyte (either macrophage or neutrophil). The phagocyte seals the pathogen in an internal phagosome into which the phagocyte releases lysozymes. These lysozymes destroy the pathogen. Remnants of proteins specific to the pathogen are transported to the phagocyte cell surface, becoming antigens to be presented to T lymphocytes. The cellular response to pathogen occurs following the activation of T lymphocytes that have the antigen specific receptor, which generate Helper T-cells, Memory T-Cells, Suppressor T cells and Killer T-cells. The helper T cells go on to clonal activation of B cells. This causes rapid division of B cells with the antibody specific to the presented antigen. Some of these B cells differentiate into memory B cells whilst the majority differentiate into plasma cells, releasing antibodies in the process. The antibody binds to the antigens any remaining pathogens causing them to clump together (called agglutination).