This detailed anatomical diagram illustrates the development of the neural tube in an embryo at days 22-23 from an anterior-superior perspective. The left panel shows the embryo with labeled structures including the neural groove, neural fold, neural crest cells, somites, notochord, brain regions, otic placode, and yolk sac. The right panel presents a cross-section of neural tube development, highlighting layers such as the surface ectoderm, mesoderm subdivisions, endoderm, developing spinal cord, neurocoel, and somite components like dermatome and myotome. Additionally, a three-step schematic at the bottom right illustrates primary neurulation, showing neural plate formation, neural fold elevation, and tube closure, with color-coded mesoderm layers for clarity.