in humans, persists as the tonsillar fossa - the endodermal lining covers the mesodermal lymphatic tissue to form the palatine tonsil[ISBN:1607950324]. the dorsal elongation of the second pouch endoderm of all mammals, with the exception of rodents, gives rise to the epithelial lining of palatine tonsils; in rodents, the ventral portion of the second pouch appears to degenerate whereas the remaining part is incorporated into the lateral border of the pharynx; it appears that rodents no longer require tonsils as their function is carried out by the NALT (Nose/Nasal-Associated Lymphoid Tissue) system in the upper respiratory tract

dorsal elongation of second pouch endoderm, dorsal pharyngeal pouch 2 endoderm, dorsal branchial pouch 2 endoderm

uberon

UBERON:0010023

• palatine tonsil
• oropharynx