Middle ear cavity is formed by pharyngeal pouch
Pouch Derivatives 1st Eustachian tube(opens into nasopharynx) and middle ear cavity 2nd Lines tonsillar crypts, forms endodermal epithelium of tonsil 3rd Dorsal - Inferior parathyroid glands Ventral - Thymus 5th fuses with 4th pouch Dorsal - Superior parathyroid glands Ventral - Ultimobranchial body recieves neural crest cells and changes to parafollicular c cells
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Pharyngeal Arches