Simplify the following text for a Grade 10 native English-speaking person.
Original: In the upper part of the vertebral column , spinal nerves exit directly from the spinal cord , whereas in the lower part of the vertebral column nerves pass further down the column before exiting .
Simplified: The spinal cord is a thin bundle of nerves that is an extension of the central nervous system from the brain and is enclosed in and protected by the bony vertebral column .