Derivatives of 2nd pharangeal arch, are the following EXCEPT:
Ans. a (Tensor palate). (Ref. Human Embryology by Inderbirsingh, 7th/pg.p 112)Branchial archesFirst arch derivatives1. Meckel's cartilageMandible,Malleus,Incus,Sphenomandibular ligament,Anterior ligament of malleus.2. Muscles(Hint--4'M', 2 'V, M and A)Four muscles of mastication (temporalis, masseter, lateral and medial pterygoids).Tensor tympani,Tensor veli palatini,Mylohyoid,Anterior belly of digastric.3. Nerve of first archMandibular nerve (post-trematic) and chorda tympani (pretrematic).4. Artery of first archMaxillary artery.Second arch derivatives1 Reichert's cartilage (Hint--4'S').Stapes,Styloid,Smaller (lesser) horn of hyoid & upper half of hyoid,Stylohyoid ligament2. MusclesMuscles of facial expression,Stapedius,Stylohyoid,Posterior belly of digastric.3. Nerve of second archFacial nerve4. Artery of second archStapedial artery.Third arch derivatives j1. CartilageGreater horn of hyoid, lower half of hyoid.2. MuscleStylopharyngeus3. Nerve of third archGlossopharyngeal nerve.Fourth arch derivatives j1. CartilagesThyroid, cricoid, arytenoids, corniculate and cuneiform.2. MusclesMost pharyngeal constrictors,Cricothyroid,Levator veli palatini.3. Nerve of fourth archSuperior laryngeal branch of vagus nerve.Fifth arch makes no major development contributions.Sixth arch derivatives1. Musclesall intrinsic muscles of larynx except cricothyroid.2. Nerve of sixth archRecurrent laryngeal branch of vagus nerve.BRANCHIAL (PHARYNGEAL) POUCH DERIVATIVES# First pouch derivatives--middle ear cavity, Eustachia tube, mastoid air cells, tongue (ant 2/3).# Second pouch derivatives--epithelial lining of palatine tonsil.# Third pouch (dorsal wings)--inferior parathyroids# Third pouch (ventral wings)--thymus# Fourth pouch derivatives--superior parathyroids.1 BRANCHIAL CLEFT DERIVATIVESFirst cleftdevelops into external auditory meatus.Second through fourth cleftsform temporary cervical sinuses, which are obliterated by proliferation of second arch mesenchyme.Note: Persistent cervical sinuscan lead to a branchial cyst in the neck.
Tensor palate
Stapedius
Digastric-posterior belly
Platysma
Pharyngeal Arches