Differences Between B-Cells and T-Cells. T cells and B cells are the major cellular components of the adaptive immune response. T cells are involved in cell-mediated immunity, whereas B cells are primarily responsible for humoral immunity.
Bcells and Tcells---This lecture is longer than most videos posted on this board, but gives a descriptive breakdown of how b cells and t cells are activated. The video goes into detail about CD4 and CD8 t cells. Also goes into detail about what happens after cells are activated.