aarista's version from 2016-06-06 04:06

aortic arch derivatives

Summary = aortic arch derivatives develop into arterial system
Question Answer
1stpart of maxillary artery (branch of external carotid). 1st arch is maximal
2ndStapedial artery and hyoid artery. Second = Stapedial
3rdCommon Cartoid artery and proximal part of internal Carotid artery. C is 3rd letter of alphabet
4thon L, aortic arch; on R, proximal part of right subclavian artery. 4th arch (4 limbs) = systemic
6thproximal part of pulmonary arteries

branchial (pharyngeal) apparatus

Question Answer
composed ofbranchial Clefts, Arches, Pouches CAP
mnemonicCAP covers outside to inside Clefts = ectoderm, Arches = mesoderm + neural crest, Pouches = endoderm
branchial cleftsderived from ectoderm. aka branchial grooves
branchial archesderived from mesoderm (muscles, arteries) and neural crest (bones, cartilage)
branchial pouchesderived from endoderm

branchial cleft derivatives

Question Answer
1st cleftexternal auditory meatus
2nd - 4th cleftstemporary cervical sinuses (obliterated by prolif of 2nd arch mesenchyme)
persistent cervical sinus becomesbranchial cleft cyst within lateral neck, anterior to SCM. immobile during swallowing

branchial arch derivatives / cartilage

Question Answer
1st archMaxillary process > Maxilla, zygoMatic bone. Mandibular process > Meckel cartilage; Mandibule, Malleus and incus, sphenoMandibular ligament
2nd archRichert cartilage-Stapes, Styloid process, lesser horn of hyoid, Stylohyoid ligament
3rd archGreater horn of hyoid
4th-6th archesArytenoids, Cricoid, Corniculate, Cuneiform, Thyroid (used to sing and ACCCT)

branchial arch derivatives / muscles

Question Answer
1st archMuscles of Mastication (temporalis, Masseter, lateral and Medial pterygoids), Mylohyoid, anterior belly of digastric, tensor tympani, tensor veli palatini
2nd archmuscles of facial expression, Stapedius, Stylohyoid, platySma, posterior belly of digastric
3rd archstylopharyngeus (think styloPHARYNGEUS innervated by glossoPHARYNGEAL nerve)
4th-6th arches4th arch - most pharyngeal constrictors; cricothyroid, levator veli palatini. 6th arch - all intrinsic muscles of larynx except cricothyroid

branchial arch derivatives / nerves

Question Answer
mnemonicAt the restaurant of the golden arches kids tend to chew (1), then smile (2), then swallow stylishly (3) or simply swallow (4) and then speak (6)
1st archCN V2 and V3 chew
2nd archCNVII (facial expression) smile
3rd archCNIX (stylopharyngeus) swallow stylishly
4th-6th arches4th arch - CN X (superior laryngeal branch) simply swallow 6th arch - CN X (recurrent laryngeal branch) speak
which arches form posterior 1/3 of tonguearches 3 and 4
Pierre Robin sequencemicrognathia, glossoptosis, cleft palate, airway obstruction
Treacher Collins syndromeneural crest dysfxn > mandibular hypoplasia, facial abnormalities

branchial pouch derivatives

Question Answer
mnemonicear, tonsils, bottom-to-top: 1 (ear), 2 (tonsils), 3 dorsal (bottom for inferior PTHs), 3 ventral (To = Thymus), 4 (top = superior PTHs)
1st pouchmiddle ear cavity, eustachian tube, mastoid air cells (1st pouch >> endoderm-lined structures of ear)
2nd pouchepithelial lining of palatine tonsil
3rd pouchdorsal wings > inferior PTHs, ventral wings > thymus (3rd-pouch structures end up below 4th pouch structures)
4th pouchdorsal wings > superior PTHs, ventral wings > ultimobranchial body, parafollicular (C) cells of thyroid
digeorge syndromechromosome 22q11 deletion. aberrant dvlpmnt of 3rd and 4th pouches > T-cell deficiency (thymic aplasia) and hypoCa++ (failure of PTH dvlpmnt). ass w/ cardiac defects (conotruncal anomalies)