Embryology — Flashcards

Flashcard 11: branchial pouches

Answer: endoderm

Flashcard 12: branchial clefts

Answer: ectoderm

Flashcard 13: The 5th aortic arch forms the _____ artery.

Answer: nothing - it degenerates

Flashcard 14: The 3rd aortic arch forms the _____ artery.

Answer: common and internal carotid

Flashcard 15: What is a vitelline fistula?

Answer: Complete failure of the vitelline duct to involute, forming a direct communication between the ileum and the umbilicus.

Extra: Clinical presentation: Fecal/meconium discharge from the umbilicus. Associated with: Persistent vitelline duct (omphalomesenteric duct).

Flashcard 16: The umbilical vein drains into the _____ via the _____.

Answer: IVC

Flashcard 17: Identify structure 7 (as shown on the image on the back)

Answer: 7: Umbilical vein::Identify the labeled structure 7

Flashcard 18: Identify 6 in the following image:

Answer: umbilical artery

Flashcard 19: What is the embryological origin of the urethral epithelium?

Answer: Endoderm (Urogenital sinus)

Extra: The epithelium of most of the urethra (both male and female) is derived from the endoderm of the urogenital sinus. The connective tissue and smooth muscle surrounding it are derived from splanchnic mesoderm. Note: The terminal part of the male urethra (glandular part in the glans penis) is derived from surface ectoderm.

Flashcard 20: Embryological origin of the kidneys (germ layer)

Answer: Intermediate mesoderm

Extra: The kidneys and gonads develop from the intermediate mesoderm. Specifically: - Metanephric diverticulum (ureteric bud) -> Ureter, renal pelvis, calyces, collecting tubules. - Metanephric blastema -> Nephrons (from Bowman capsule to distal convoluted tubule).