The nucleus ambiguus is associated with which two structures?

The nucleus ambiguus is associated with which two structures?

• A. Pharynx and Larynx
• B. Pharynx and Esophagus
• C. Larynx and Tongue
• D. Esophagus and Trachea

Answer: (A)

The nucleus ambiguus contains the motor neurons that innervate the skeletal (branchial) muscles of the pharynx and larynx via cranial nerves IX and X. It sends the motor commands to muscles like the stylopharyngeus (from IX) and the constrictors of the pharynx plus most intrinsic muscles of the larynx (from X). Because it controls these pharyngeal and laryngeal muscles, it’s most closely associated with function in the pharynx and larynx. It does not supply the esophagus (which is controlled by autonomic pathways from the dorsal motor nucleus of the vagus), the tongue (hypoglossal nucleus), or the trachea.

The nucleus ambiguus contains the motor neurons that innervate the skeletal (branchial) muscles of the pharynx and larynx via cranial nerves IX and X. It sends the motor commands to muscles like the stylopharyngeus (from IX) and the constrictors of the pharynx plus most intrinsic muscles of the larynx (from X). Because it controls these pharyngeal and laryngeal muscles, it’s most closely associated with function in the pharynx and larynx. It does not supply the esophagus (which is controlled by autonomic pathways from the dorsal motor nucleus of the vagus), the tongue (hypoglossal nucleus), or the trachea.