Label the following components of the corticospinal tracts with numbers 1 through 6, with 1 being the origin of the tracts and 6 their destination.
_____ Medullary pyramids where most fibers decussate.
_____ Anterior horn of the spinal gray matter.
_____ Midbrain and pons.
_____ Upper motor neurons in the primary motor and premotor cortices.
_____ Corona radiata and internal capsule.
_____ Lateral funiculus of the spinal cord.