Final answer:
The second neuron of the corticospinal tract, which is the lower motor neuron, is located in the spinal cord's ventral horn, where it synapses with other neurons to control skeletal muscle movements.
Step-by-step explanation:
The second (lower) neuron of the corticospinal tract is located in the ventral horn of the spinal cord. This lower motor neuron originates in the primary motor cortex within the frontal lobe, specifically the precentral gyrus, and travels down through various structures of the central nervous system including the midbrain, pons, and medulla. Eventually, it reaches the spinal cord, where it enters the ventral horn. At the appropriate level in the ventral horn, it finally synapses with the target lower motor neurons which are responsible for causing muscle fibers to contract and thus control the skeletal muscle movements.