EMBRYOLOGY OF THE ANTERIOR ABDOMINAL WALL

- WEEK 5

• The following structures pass through the primitive umbilical ring.
• Connecting stalk (containing the allantois and umbilical vessels).
• Yolk stalk (vitelline or omphalomesenteric duct).
• The canal (connecting intra and extracoelomic embryonic cavities).
• Ring constricts and crowds the above contents together.
• Amniotic cavity enlarges and amnion envelops the connecting and yolk sac stalks forming the primitive umbilical cord.
• Cord contains - yolk sac stalk
• Umbilical vessels
• Remnants of allantois
• Some intestinal loops.