Cranial nerves III (oculomotor), VII (facial), and IX (glossopharyngeal) supply the entire parasympathetic innervation of the head; however, only the preganglionic fibers lie within these three pairs of cranial nerves.

Question

Quizplus · Accepted Answer

Cranial nerves III, VII, and IX only carry the preganglionic fibers, which synapse with postganglionic neurons in nearby ganglia before innervating the target organs. Therefore, while these three pairs of cranial nerves provide parasympathetic innervation to the head, they do not supply the entire pathway.

Cranial Nerves III (Oculomotor), VII (Facial), and IX (Glossopharyngeal) Supply