Embryology-Endocrine Flashcards
How does the pituitary gland form?
The infundibulum pouches out from the diencephalon, Rathke’s pouch comes out from the oral ectoderm. Finally, the pars tuberalis wraps around the infundibulum
How do the thyroid and parathyroid glands ultimately join up?
The thyroid gland migrates down from the foramen cecum through the thyroglossal duct. The inferior parathyroid gland migrates from pharyngeal pouch 3. The superior parathyroid gland migrates from pharyngeal pouch 4.
Where do the parafollicular cells in the thyroid migrate from?
The ultimobranchial body
Where do thyroglossal cysts typically form?
Along the path of the thyroglossal duct, where the thyroid migrated during development.
How do the adrenal glands form?
The fetal cortex (from mesoderm) forms, dissolves and then the definitive cortex forms. The chromaffin cells surround the definitive cortex and eventually become the medulla (from neural crest). Then the kidneys ascend to be right beneath them.
How does the pancreas form?
A dorsal and ventral pancreatic bud form. The ventral portion comes to lie beneath and behind the dorsal pancreatic duct. Their ducts fuse and form the pancreas with ducts and acini forming the exocrine pancreas and islets of Langerhans branching from the acini to form the endocrine pancreas.
How do the genitals form?
Primordial germ cells migrate from the yolk sac to the genital ridge. They seed the primitive sex cords (derived from proliferating body epithelium) in the genital ridge to form the mature gonads. Males have testes determining factor that forms testes, Leydig cells (testosterone producers) and Sertoli cells (Mullerian-inhibiting factor producers). Females form follicular cells (estrogen producers) and luteal cells (progesterone producers)
Where do these different adult structures originate from in the developing embryo?
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