Which statement about the nucleus ambiguus is true?

Which statement about the nucleus ambiguus is true?

• A. It primarily controls visceral muscles
• B. It is located in the spinal cord
• C. It mediates swallowing and phonation via pharynx and larynx
• D. It innervates limb muscles

Answer: (C)

The nucleus ambiguus is a motor nucleus in the medulla that provides the nerves to the pharyngeal and laryngeal muscles via cranial nerves IX and X. These muscles enable swallowing and phonation, so this nucleus specifically mediates swallowing and voice production through the pharynx and larynx. It does not control visceral smooth muscle (that’s autonomic), isn’t in the spinal cord (it’s in the medulla), and doesn’t innervate limb muscles (that’s done by spinal motor neurons).

The nucleus ambiguus is a motor nucleus in the medulla that provides the nerves to the pharyngeal and laryngeal muscles via cranial nerves IX and X. These muscles enable swallowing and phonation, so this nucleus specifically mediates swallowing and voice production through the pharynx and larynx. It does not control visceral smooth muscle (that’s autonomic), isn’t in the spinal cord (it’s in the medulla), and doesn’t innervate limb muscles (that’s done by spinal motor neurons).