Embryology Flashcards
During embryological development, which of the following represent the correct origin of the pancreas?
Ventral and dorsal endodermal outgrowths of the duodenum
Ventral and dorsal outgrowths of mesenchymal tissue from the posterior abdominal wall
Ventral and dorsal outgrowths of the vitellointestinal duct
Ventral and dorsal biliary tract diverticulae
Buds from inferior aspect of caudate lobe
Ventral and dorsal endodermal outgrowths of the duodenum
The ventral arises close to, or in common with the hepatic diverticulum, and the larger, dorsal outgrowth arises slightly cranial to the ventral extending into the mesoduodenum and mesogastrium.
When the buds eventually fuse the duct of the ventral rudiment becomes the main pancreatic duct.
A 1 year old boy is referred because of an impalpable testis in the left scrotum. Which of the following positions describes an ectopic testis?
Intracanalicular At superficial ring At deep inguinal ring Upper scrotum At base of penis
At base of penis
A testis at the base of the penis is ectopic, not listed is the superficial inguinal pouch (one of the commonest ectopic sites).
A testis located at deep or superficial rings or intra canalicular is not ectopically located.
From which embryological structure is the ureter derived?
Uranchus Cloaca Vitello-intestinal duct Mesonephric duct None of the above
Mesonephric duct
The ureter develops from an outpouching that arises from the mesonephric duct. The mesonephric duct is associated with the metanephric duct that develops within the metenephrogenic blastema. This forms the site of the ureteric bud which branches off the mesonephric duct.
A 7 year old boy presents with right iliac fossa pain and there is a clinical suspicion that appendicitis is present. From which of the following embryological structures is the appendix derived?
Vitello-intestinal duct Urachus Foregut Midgut Hindgut
Midgut
It is derived from the midgut which is why early appendicitis may present with periumbilical pain.
