Final answer:
Postganglionic axons in the sympathetic nervous system are unmyelinated and directly influence the target organ.
Step-by-step explanation:
In the sympathetic nervous system, postganglionic axons are unmyelinated. Unlike the myelinated preganglionic fibers, postganglionic fibers are longer as they travel from the ganglion to the target effector. These unmyelinated postganglionic fibers directly influence the organ they project to.