What function does the intervertebral disc serve?

The intervertebral disc primarily serves the function of cushioning between vertebrae. These discs are composed of a tough outer layer called the annulus fibrosus and a gel-like center called the nucleus pulposus. Their design allows them to absorb shock and distribute pressure evenly when the spine undergoes various stresses from movement and weight-bearing activities. This cushioning effect is crucial for maintaining spinal health, as it reduces the impact of forces on the vertebrae during activities such as walking, running, and jumping.

While intervertebral discs do contribute indirectly to spinal movement by allowing for flexibility and movement between the vertebrae, their main functionality lies in their ability to provide support and cushioning. The other options highlight different aspects of spinal anatomy and function, but none of them reflect the primary role of the intervertebral discs as effectively as cushioning between vertebrae. This understanding of the intervertebral disc's role is essential for grasping basic spinal mechanics and injury prevention in sports medicine.