Question

Explain the changes that the different parts of the embryo undergo after implantation up till formation of three germ layers.

Answer 1

The embryo's inner cell mass (ICM) forms the embryonic disc after implantation, and it proceeds through gastrulation to produce three germ layers:

1. Ectoderm: Forms the nervous system and epidermis.
2. Mesoderm: Forms muscles, bones, blood vessels, and internal organs.
3. Endoderm: Forms the lining of the digestive and respiratory tracts and associated glands.

These germ layers give rise to all tissues and organs of the body.