Which one of the following is NOT true of the corticospinal tracts? most of their neurons cross to the opposite side of the cord in the medulla.
they carry motor nerve impulses.
their neuron cell bodies lie in the precentral gyrus.
they travel the cord as lower motor neurons.

not: both offer magnification to the atomic level.

the law of original horizontality explains:   why rocks appear in layers. correct answer: b the law suggests that all rock layers are originally laid down (deposited) horizontally and can later be deformed.   the principle is used by geologists to make assumptions about the relative ages of sedimentary rocks.