Assertion (A): Little rotation and bending of the vertebral column is possible. Reason (R) : This is due to the presence of fibrous joints between vertebrae.

Assertion (A) is true as the vertebral column allows for limited rotation and bending. While individual movements between adjacent vertebrae are small, they summate along the column to provide significant flexibility [t4][t5]. However, Reason (R) is false. The joints between vertebral bodies are not fibrous joints; they are cartilaginous joints (specifically symphyses) containing intervertebral discs made of fibrocartilage [t1][t2][t5]. Fibrous joints, such as sutures in the skull, are generally immobile [t5][t8]. The vertebral column also contains synovial joints (zygapophysial or facet joints) between the vertebral arches, which facilitate and guide movement [t1][t3]. Because the primary connection between the vertebral bodies is cartilaginous rather than fibrous, the reason provided is anatomically incorrect.

Sources

1. [1] https://www.seslhd.health.nsw.gov.au/sites/default/files/groups/POWHED/docs/Jack-Marjot-Notes/Anatomy/THEVERTEBRALCOLUMN.pdf
2. [2] https://www.ncbi.nlm.nih.gov/books/NBK507893/
3. [3] https://www.ncbi.nlm.nih.gov/books/NBK459153/