| Q: How does the specific defense of the immune system work? A: When a pathogen enters the system, it is investigated by B-cells specific for many different things. If a B-cell happens to be present which is specific for that pathogen, the cell will replicate and then produce its particular kind of antibodies. These antibodies bind to the antigens on the pathogens, causing the antigens to clump together. These clumps are then destroyed by the rest of the immune system. If the pathogen (most likely a virus) enters human body cells, the antigens get broken down inside the cell, and the pieces of the antigen are presented on the surface of the cell. If a T-cell is present which is specific for those pieces specific for that pathogen, the T cell will replicate and then bond to these infected cells and kill them to keep the virus inside the cell from spreading. The immune system reacts faster to a pathogen if its been exposed to that pathogen before. Push play to hear the answer. |
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