Osmosis video - Development of the digestive system and body cavities

https://osmosis.org/learn/Developmentofthedigestivesystemandbody_cavities The primitive digestive system starts developing at around week 3 in the embryo. The primitive gut starts to form when the yolk sac becomes incorporated into the embryo. It then forms a blind-ended tube, which becomes the foregut on the cephalic end, and the hindgut on the caudal end. The middle part of the midgut also forms but remains temporarily attached to the yolk sac via the vitelline duct (yolk stalk). The accessory organs of the digestive system form as outpouchings alongside the primitive gut tube.