This undifferentiated embryonic structure then undergoes a phase of major cell migration called gastrulation, producing a gastrula with three separate germ layers: the endoderm, mesoderm, and ectoderm. Endoderm The endoderm is formed from cells that migrate toward the center of the developing gastrula.
The Eiffel tower is made of puddled iron. It is made up of steel in steel X's. The Eiffel Tower is made of iron. The Eiffel Tower is made of pure iron.
The Eiffel Tower, La Tour Eiffel in French, was the main exhibit of the Paris Exposition â or World's Fair â of 1889. It was constructed to commemorate the centennial of the French Revolution and to demonstrate France's industrial prowess to the world.