Specific Arches
There are six pharyngeal arches, but in humans the fifth arch only exists transiently during embryologic growth and development. Since no human structures result from the fifth arch, the arches in humans are I, II, III, IV, and VI.
More is known about the fate of the first arch than the remaining four. The first three contribute to structures above the larynx, while the last two contribute to the larynx and trachea.
| Pharyngeal arch | Muscular contributions | Skeletal contributions | Nerve | Artery |
| 1st (also called "mandibular arch") | Muscles of mastication, anterior belly of the digastric, mylohyoid, tensor tympani, tensor veli palatini | Maxilla, mandible (only as a model for mandible not actual formation of mandible), the incus and malleus of the middle ear, also Meckel's cartilage | Trigeminal nerve (V2 and V3) | Maxillary artery, external carotid artery |
| 2nd (also called the "hyoid arch") | Muscles of facial expression, buccinator, platysma, stapedius, stylohyoid, posterior belly of the digastric | Stapes, styloid process, hyoid (lesser horn and upper part of body), Reichert's cartilage | Facial nerve (VII) | Stapedial artery, hyoid artery |
| 3rd | Stylopharyngeus | Hyoid (greater horn and lower part of body), thymus, inferior parathyroids | Glossopharyngeal nerve (IX) | Common carotid, internal carotid |
| 4th | Cricothyroid muscle, all intrinsic muscles of soft palate including levator veli palatini | Thyroid cartilage, superior parathyroids, epiglottic cartilage | Vagus nerve (X), superior laryngeal nerve | Right 4th aortic arch: subclavian artery
Left 4th aortic arch: aortic arch |
| 6th | All intrinsic muscles of larynx except the cricothyroid muscle | Cricoid cartilage, arytenoid cartilages, corniculate cartilage | Vagus nerve (X), recurrent laryngeal nerve | Right 6th aortic arch: pulmonary artery Left 6th aortic arch: pulmonary artery and ductus arteriosus |
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