The notochord plays a critical signaling role in early development. After its inductive function is complete, it persists in the adult as which structure?

• A Ligamentum flavum connecting adjacent laminae
• B Anterior longitudinal ligament of the vertebral column
• C Filum terminale of the spinal cord
• D Nucleus pulposus at the center of each intervertebral disc ✓

Explanation

The notochord induces the overlying ectoderm to form the neural plate (primary neurulation) and the surrounding mesoderm to form the vertebral bodies (sclerotomes). After this inductive role, the notochord degenerates within the vertebral bodies but persists within each intervertebral disc as the nucleus pulposus — the gelatinous central component that provides hydrostatic pressure resistance to axial loads. A chordoma is a malignant tumor of notochordal remnants. The filum terminale is derived from the ependymal cells of the terminal spinal cord.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.