As we have seen, a cell dying of necrosis struggles violently, with everything at its disposal, to avoid death. The act of suicide by a cell is completely different. One cannot help but be struck by how peaceful a death it seems, and all in all a rather unmessy one. Although it may involve large numbers of cells at a given location, the cells do not explode as a result of osmotic imbalance. For example, when a T-lymphocyte comes upon a susceptible cancer cell, it attaches briefly to the cell and withdraws, whereupon the cancerous cell quietly disintegrates.
Apoptosis is also important to embryologic development.
Cells that are produced in surplus during development are eliminated in this manner. Sexuality exists to provide the widest selection possible of genetic possibilities while allowing for the repair and correction of genetic misinformation. Sex saves our germinal cells, but all of our somatic cells will inevitably die, either by illness or accident or inevitably by senescence and programmed self-destruction. Old age and death are the price we must pay for the complexity of multicellular life. Our somatic cells exist only to support the needs of our germinal cells.