ANATOMY

Detailed explanation-1: -The sixth pharyngeal arch forms the laryngeal cartilages, the intrinsic muscles of the larynx, the pulmonary arteries and the ductus arteriosus. There are no bones and ligaments in this pharyngeal arch.

Detailed explanation-2: -There are five pairs of pharyngeal arches in humans, and other amniotes, and these are numbered, from anterior to posterior, 1, 2, 3, 4 and 6 (Fig. 1). The 1st, most anterior, arch will form the jaws and the muscles of mastication, as well as the incus and malleus. This arch is innervated by the trigeminal nerve.

Detailed explanation-3: -During human, and all vertebrate development, a series of pharyngeal arch pairs form in the developing embryo.

Detailed explanation-4: -arch 1: CN V (trigeminal) arch 2: CN VII (facial) arch 3: CN IX (glossopharyngeal) arch 4: CN X (superior laryngeal branch of the vagus) arch 6: CN X (recurrent laryngeal branch of the vagus)