Embryology USMLE Step 1 Practice Question
While examining a newborn baby in the nursery, a physician notes that urine is draining from the umbilicus. Contrast dye is introduced into the bladder through the urethra, and it is confirmed radiologically that dye is passing to the umbilicus. Which of the following embryonic structures has abnormally persisted in this patient?
Answer choices
- AMesonephric duct
- BMesonephric tubules
- CUrorectal septum
- DAllantoic ductCorrect answer
- EUreteric bud
- FPersistent omphalomesenteric duct
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