According to the bell magendie law, " the ventral spinal roots transmit motor impulses and the posterior roots sensory impulses,which establish a major landmark in the history of neuroscience."
The nature and physiology of the phenomena were described independently by sir charles bell , he is British anatomical scientist and french physiologist francois magendie after that Johannes peter muller confirmed it.
The ventral roots preganglionic sympathetic fibers of the atomic nervous system exit the spiral cord with ventral roots T1 through L2. It consist predominately of efferent somatic motor fibers. There are also 31 pairs of spinal nerves and roots. Eight pairs of cervical nerves exit the cervical cord at each vertebral level.
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