Question

cranial origin of the parasympathetic nervous system
which cranial nerve is not involved in the parasympathetic nervous system?
oculomotor nerve (cn iii)
hypoglossal nerve (cn xii)
facial nerve (cn vii)
vagus nerve (cn x)

Explanation:

The parasympathetic nervous system has cranial components from certain cranial nerves. The oculomotor nerve (CN III) innervates the ciliary muscle (for accommodation) and the sphincter pupillae (for pupil constriction), which are parasympathetic functions. The facial nerve (CN VII) has parasympathetic fibers that innervate the lacrimal gland (tear production) and sub - mandibular and sub - lingual salivary glands. The vagus nerve (CN X) has extensive parasympathetic innervation to thoracic and abdominal viscera (e.g., heart rate regulation, digestive organ innervation). The hypoglossal nerve (CN XII) is a motor nerve that innervates the muscles of the tongue and has no role in the parasympathetic nervous system.

Answer:

B. Hypoglossal nerve (CN XII)