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spinal root
spinal root A spinal root is one of a pair of bundles of nerve fibers that enter or leave the spinal cord at each spinal segment.
A spinal root is one of a pair of bundles of nerve fibers that enter or leave the spinal cord at each spinal segment. The dorsal root mainly carries sensory signals toward the cord, and the ventral root mainly carries motor and autonomic output away from it; together they form a mixed spinal nerve.