Question

formation of ectoderm​

Answer 1

Answer:

The ectoderm originates in the epiblast, and is formed during gastrulation. Once the mesoderm forms, cells cease to ingress into the primitive streak; the remaining epiblast cells are hereafter called ectoderm.

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Answer 2

Answer:

Explanation:

The ectoderm originates in the epiblast and is formed during gastrulation. Once the mesoderm forms, cells cease to ingress into the primitive streak; the remaining epiblast cells are hereafter called ectoderm. The endoderm is one of the germ layers formed during animal embryonic development. Cells migrating inward along with the archenteron form the inner layer of the gastrula, which develops into the endoderm. The endoderm consists at first of flattened cells, which subsequently become columnar.