Final answer:
The fasciculus gracilis is the medial division of the dorsal column system that carries sensory information from the lower body, while the fasciculus cuneatus is laterally positioned and carries information from the upper body.
Step-by-step explanation:
The fasciculus gracilis is a structure within the dorsal column system of the spinal cord that carries sensory information from the lower half of the body. It is positioned medially within the dorsal columns. The dorsal column system starts when axons from the dorsal root ganglion enter the spinal cord and organize themselves such that those from lower body levels are medial, whereas those from higher body levels are lateral.
The dorsal column is divided into two tracts: the fasciculus gracilis medially and the fasciculus cuneatus laterally, with the latter carrying fibers from sensory neurons in the upper body. The medial positioning of the fasciculus gracilis provides a pathway for sensory signals from the lower body to reach the nucleus gracilis in the medulla, which then synapses with the second neuron in the pathway.