A. 1st pharyngeal arch.
B. 2nd pharyngeal arch.
C. 3rd pharyngeal arch.
D. 4th pharyngeal arch.
Ans:D. 4th pharyngeal arch.
The structure marked as A in the picture above represents the epiglottis.
DERIVATIVES OF PHARYNGEAL ARCH
|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||Premaxilla, maxilla, mandible (only as a model for mandible not actual formation of mandible), zygomatic bone, part of the temporal bone,the incus, and the malleus of the middle ear, also Meckel’s cartilage and the sphenomandibular ligament.||Trigeminal nerve(part of 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, auricular||Stapes, temporal styloid process, hyoid bone (lesser horns and upper part of body), stylohyoid ligament, Reichert’s cartilage||Facial nerve (VII)||Stapedial artery, hyoid artery|
|3rd||Stylopharyngeus||Hyoid bone (greater horns and lower part of body), thymus||Glossopharyngeal nerve (IX)||common carotid, internal carotid|
|4th||Cricothyroid muscle, all intrinsic muscles of soft palate (including levator veli palatini) except tensor veli palatini||Thyroid cartilage, epiglottic cartilage||Vagus nerve (X), superior laryngeal nerve||Right 4th aortic arch: subclavian arteryLeft 4th aortic arch: aortic arch|
|6th||All intrinsic muscles of larynx except the cricothyroid muscle||Cricoid cartilage, arytenoid cartilages, corniculate cartilage, cuneiform cartilages||Vagus nerve (X), recurrent laryngeal nerve||Right 6th aortic arch: pulmonary arteryLeft 6th aortic arch: pulmonary artery and ductus arteriosus|