A fertilized egg is a single cell. As it progresses in cell division,
not only does the number of cells increase but various cells with different
properties are created. What
mechanisms produce such different properties of the cells? To
conduct research on developmental engineering, we must understand the process
by which the body is created from an actual fertilized egg. The elucidation of
such mechanisms may allow us to produce individuals from isolated cells. The
actual body has “somatic line cells” that make up the body and “germ-line cells”
that produce gametes for the next generation.