Biology · ANIMAL KINGDOM

In the structural schematic of a typical chordate shown in Figure 4.16, identify the relative spatial arrangement of the central nervous structure and the skeletal axis along the dorso-ventral plane.

1. A
   The nerve cord is ventral and solid, situated below the dorsal cartilaginous notochord
2. B
   The notochord lies dorsally above the nerve cord, which surrounds the pharyngeal slits
3. C
   The hollow nerve cord lies dorsally, directly above the solid longitudinal notochord
4. D
   The nerve cord and notochord are fused together ventral to the alimentary canal