The motor nerve fibers in the anterior or ventral nerve root which is present in the anterior column of gray matter situated in the spinal cord, axons of nerve cells situated in the areas of thoracic and lumbar and axons of cells situated in the lateral columns of gray matter of sympathetic nerve fibers.
Posterior or dorsal nerve root:
There are sensory nerve fibers in the root of posterior or dorsal nerve root.
The nerves which come out from the both roots become one by meeting altogether inside the vertebral canal and come out through the intervetibral foramen. After coming out, each spinal nerve gets divided into anterior and posterior ramus. Posterior rami supply muscles and skin of head, neck and back portion of hip and anterior rami which are longer comparatively supply anterior and lateral portion of neck, hip and hand and feet.
Anterior rami make big nets or plexus by meeting with the branches of other spinal nerves. Five big plexus of mixed nerves come into existence each side of vertebral column by leaving thoracic area.