1.1.1. Derivatives of PharyngealPouchesMaxillaryprocess.1) 1st pouchMandibularprocessPrim.tympanicPharyngealLateral → tympanicPharyngealcavitypouchescleftscavityExt.PharyngotympanicauditorytubemeatusMedial-PalatinetonsilpharyngotympanictubeParathyroidgland (inf.)ThymusParathyroidCervicalgland (sup.)sinusUltimo-branchialEpicardialbodyridgeB
1.1.1. Derivatives of Pharyngeal Pouches 1) 1st pouch Lateral → tympanic cavity Medial → pharyngotympanic tube
2)2nd pouchtonsillar fossa, surface epithelium of palatinetonsilMaxillary3) 3rd pouchprocessMandibularprocessDorsal part -PrimtympanicPharyngealPharyngealcavityinferiorcleftspouchesExt.-PharyngotympanicauditorytubeparathyroidsmeatusPalatinetonsilVentral part Parathyroidgland (inf.)thymusThymusParathyroidCervicagland (sup.)Both migratesinusUltimo-branchialEpicardialbodyridgecaudally.B
3) 3rd pouch Dorsal part → inferior 2) 2nd pouch → tonsillar fossa, surface epithelium of palatine tonsil inferior parathyroids Both migrate caudally. Ventral part → thymus
4) 4th pouchDorsal →superior parathyroidsVentral →degeneratesMaxillaryprocessMandibularprocessPrim.tympanicPharyngealPharyngeal5)5thpouch→cavitypouchescleftsExt.Pharyngotympanicauditorytubeultimobranchial bodymeatusPalatinetonsilparafollicular cellsParathyroidgland (inf.)(in thyroid)ThymusParathyroidCervicalgland(sup.)sinusUitimobranchialEpicardialbodyridgeB
4) 4th pouch Dorsal → superior parathyroids. Ventral → degenerates 5) 5th pouch → ultimobranchial body →parafollicular cells (in thyroid)
1.1.2 development of thyroid原始咽 a median thickening ofthe endoderm on thefloor of the embryonic甲状舌管退化pharynx甲状腺a bilobular sacculationthyreoglossal ductforamen cecum胸腺See flashPersistence ofthyreoglossalduct?
1.1.2 development of thyroid • a median thickening of the endoderm on the floor of the embryonic pharynx • a bilobular sacculation • thyreoglossal duct • foramen cecum Persistence of thyreoglossal duct? See flash
Brief summaryPharyngotympanic tubePrimarytympanic-Ventral sidecavityofpharynxExt.auditoryForamencecummeatusPalatinetonsilSup.parathyroidgland(from4thpouch)-ThyroidInf.parathyroidglandgland(from3rdpouch)Uitimobranchialbody-ForegutThymusSeeflash
Brief summary See flash