Santa Clara is the most populous county in the San Francisco Bay Area and in Northern California, and is one of the most affluent counties in the United States.
Spinal cord. 1  The spinal cord, about 45 cm in length, extends from the foramen magnum, where it is continuous with the medulla oblongata, to the level of the first or second lumbar vertebra (The range is T12 to L3). Below that level, the vertebral canal is occupied by spinal nerve roots and meninges.
In Depth: Spine. The spinal cord begins at the base of the brain and extends into the pelvis. Many of the nerves of the peripheral nervous system, or PNS, branch out from the spinal cord and travel to various parts of the body.