overlaps overlaps pharyngeal arch 4 pharyngeal arch 5 pharyngeal pouch pharyngeal pouch 4 A pouch that is situated between the 4th and 5th pharyngeal arch. [ISBN:0124020607][VHOG] UBERON:0007125 fourth arch pharyngeal pouch EHDAA2:0000091 EFO:0003637 4th pharyngeal pouch endoderm 4th arch branchial pouch endoderm SCTID:362858001 Fourth of the pharyngeal (endodermal) evaginations between the visceral arches from which the Eustachian tube is derived; pouches 2-4 open as gill slits.[AAO] fourth pharyngeal pouch VHOG:0000578 A conserved feature of all vertebrate embryos is the presence of a series of bulges on the lateral surface of the head, the pharyngeal arches; it is within these structures that the nerves, muscles and skeletal components of the pharyngeal apparatus are laid down. The pharyngeal arches are separated by endodermal outpocketings, the pharyngeal pouches.[well established][VHOG] VHOG:0000971 FMA:295688 fourth visceral pouch AAO:0011117 pharyngeal pouches 4 XAO:0000254 NCIT:C34181 4th arch branchial pouch Derivatives include: superior parathyroid glands and ultimobranchial body which forms the parafollicular C-Cells of the thyroid gland. Musculature and cartilage of larynx (along with the sixth pharyngeal pouch)[WP] in most mammals, excluding rodents, the dorsal part of each fourth pouch develops into a superior parathyroid gland (parathyroid IV), which lies on the dorsal surface of the thyroid gland (the parathyroid glands derived from the third pouches descend with the thymus and are carried to a more inferior position than the parathyroid glands that are derived from the fourth pouches); the elongated ventral part of each fourth pouch develops into the ultimopharyngeal body, which fuses with the thyroid gland, giving rise to the calcitonin-producing parafollicular or C-cells of the thyroid gland. In the mouse, but also in the rat and hamster, the dorsal fourth pouch does not generate a parathyroid. Thus, rodents develop only one pair of parathyroid glands. fourth branchial pouch Wikipedia:Pharyngeal_pouch_(embryology)#Fourth_pouch visceral pouch 4 4th branchial pouch TAO:0001134 UMLS:C0231071 RETIRED_EHDAA2:0000090 ZFA:0001134 EMAPA:16766 A pharyngeal pouch between pharyngeal arch 4 and arch 5 or 6 (a fifth arch never establishes in amniotes).