The ectoderm is one of the three primary germ layers formed during embryonic development. It is the outermost layer and gives rise to various structures in the body, including the skin, hair, nails, and the nervous system. The ectoderm plays a crucial role in the formation of sensory organs and the lining of the mouth and nose. During the process of gastrulation, the ectoderm is established alongside the mesoderm and endoderm. Each of these layers contributes to different tissues and organs in the developing embryo. The ectoderm's development is essential for proper growth and function of the central nervous system and other external features.