So we said that epitosis is known as programmed cell death. This is basically when a set of special enzymes initiate the process of cell death. Now why would we ever want to actually kill off our cells? Well one reason is if our cell is infected by some type of pathogen, if we have an infected cell we don't want that infected cell to infect other healthy cells. And so we want to kill off that cell. And this is the process that helps us basically kill off that cell.