How can the morphology of embryo be explained

Question

After the neurula phase and from its ventral part to the dorsal how can the morphology of embryo be explained?

Answer 1

In a schematic longitudinal part of the embryo after the neurula phase, the outermost layer of cells is the ectoderm. In ventral area comes the archenteron tube made up of endodermal cells. In both sides of embryo, coeloms delimited by mesoderm are existed. In the central area above the archenteron and in the middle of coeloms there is notochord. In the dorsal area just over the notochord lies the neural tube.