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.
To support his colossal sculpture, Bartholdi called upon the structural engineering skills of Gustave Eiffel, who designed the skeleton for its skin of copper. This was sort of a trial run for Eiffel's Tower, which was to come about five years later. The Lady's skeleton is made from about 250,000 lbs of puddled iron.