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Although they will have features in common, no two of our 26 vertebrae are exactly alike in shape, size, or function. This is hardly surprising if we consider, for example, that the cervical vertebrae do not supports ribs, while the thoracic vertebrae (upper trunk, or chest) do support them.
But for a sample vertebra, let us pick a rib-carrying vertebra, if for no other reason than that it lies about midway along the backbone. If viewed from above or below, a thoracic vertebra, like most of the others, would look like a roundish piece of bone with roughly scalloped edges on the side facing outward toward the surface of the back, and would reveal several bony projections. These knobby portions of a vertebra- some of which you can feel as bumps along your backbone- are called processes. They serve as the vertebra's points of connection to muscles and tendons, to ribs, and to other vertebrae above and below.
A further conspicuous feature is a hole, more or less in the middle of the typical vertebra, through which passes the master nerve bundle of our bodies, the spinal cord, running from the base if the skull to the top of the pelvis. thus, one of the important functions of the backbone is to provide flexible, protective tubing for the spinal cord.
Between the bones of one vertebra and the next is a piece of more resilient cartilage that acts as a cushion or shock absorber to prevent two or vertebrae from scraping or bumping each other if the backbone gets a sudden jolt, or as the backbone twist and turns and bends. these pieces of cartilage are the inter vertebral disk- infamous for pain and misery if they become ruptured or slipped disks.
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