Cell Death: A Requirement for Embryo Survival

If someone were to tell you that cell death is a necessity in order for an embryo to develop properly, you may think that they were crazy.  This may seem counterintuitive.  It appears that it would only make sense for cells to be continuously growing and dividing during development, instead of killing themselves.  However, programmed cell death, known as apoptosis, is now recognized as not only normal, but as a requirement of proper development.