Final answer:
The ectoderm germ layer is responsible for the development of the central nervous system, as well as the epidermis, hair, and nails. This development happens during neurulation when the neural plate forms and then folds to create the neural tube.
Step-by-step explanation:
The ectoderm is the primary germ layer responsible for giving rise to the cells that eventually became the central nervous system. This layer also forms other structures, such as the epidermis, hair, and nails. The development of these systems from the ectoderm occurs through a process known as neurulation, during which specialized neuroectodermal tissues along the length of the embryo thicken into the neural plate, and the subsequent formation of the neural tube.
Furthermore, it is true that the nervous system and skin cells (epidermis) develop from the same germ layer, which is the ectoderm. This layer is one of the three germ layers formed during gastrulation, with the other two being the mesoderm and the endoderm, which give rise to different tissues and organs within the body.