 All right, did you do this? Does yours look just like this? I tried to make it so that I kept them sort of on the same side. I tried to highlight similar cells with color. If you'll notice, my, this is supposed to be purple cells are naive cells, so both B cells and T cells start out as naive. The B cells, what's relevant is that they bind, the antigen binds with their antibody receptor, they endocytose that, and then they present it out on an MHC2 platform. Meanwhile, the naive T cell doesn't have anything to do with its antigen except it binds to the MHC2 platform of a dendritic cell that's holding its antigen. The naive T cell binds to the antigen and the MHC2, and that initiates activation. The activated T cell can differentiate, depending on the nature of the cell, it will either become a helper T cell, a memory T cell, or a killer T cell. If it becomes a helper T cell, this guy has the same receptor. It goes over to the B cell pattern, finds a naive B cell that's presenting the antigen on an MHC2 platform. The helper T binds to the MHC2 platform and the antigen that activates the naive B cell, and it becomes an activated B cell. The activated B cell can now differentiate into two types of cells, it can be a memory cell, or it can be a plasma cell. Plasma cells experience clonal expansion, they go crazy, and they start producing mad antibodies against this very specific guy. And so you end up with a huge number of antibodies that are going to bind with that antigen. Antibodies can act as opsonins, so they can act as triggers for phagocytosis, so that our non-specific phagocytes can just go around and yumptialize things that have antibodies stuck to them. So these antibodies, and they're going to initiate complement, they're going to help pop cells, the antibodies are definitely going to send a message that we are having an immune response. The activated T cell, one of them became the helper T, one of them became the memory T, and then one of them becomes the primary effector cell, which is the killer T. And the killer T is what goes out, its T cell receptor, I should draw that in there because it does have one, its little T cell receptor binds to MHC1 on JoCell, and its specific antigen. So if any cell in the body that's presenting the specific antigen and its MHC1 platform will be a target for the killer T cell to initiate apoptosis via granzymes and perforin. Whoa, was that cool? I think that was cool. Okay, you think that of course this has to be, this has to have something to do with homeostasis, right? So take a minute and think through, like if you are going to defend yourself in making a claim that this was related to homeostasis, I want you to think about how you're going to defend that, and I will be right back to tell you how I defend that.