Spinal Cord
A diagram of the human nervous system.
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The spinal cord is a long, thin, tubular structure made up of nervous tissue that extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone) of vertebrate animals.
The center of the spinal cord is hollow and contains a structure called central canal, which contains cerebrospinal fluid. The spinal cord is also covered by meninges and enclosed by the neural arches.
Together, the brain and spinal cord make up the central nervous system (CNS).