Answer: The Ectoderm
Explanation:
Ectoderm is one of three germ layers that forms early during the embryonic life of most animals, it is from it organs and tissues form. In a developing embryo, gastrulation occurs and the embryo reorganizes itself into the three germ layers: endoderm, ectoderm, and mesoderm. After gastrulation, comes neurulation, which starts the development of nervous system.
It is in this part the ectoderm differentiates into 2 parts; surface ectoderm: responsible for the outer surface tissue like epidermis.
Then neuroectoderm: which forms the Nervous system of the embryo
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