DIVERGENCE -

1. In it blastomeres move in different directions i.e. inside the blastocoel the blastomeres move in different directions.
2. The blastomeres which move inside i.e. the involuted blastomere are called chordamesoderm.
3. Chorda-mesoderm forms complete Notochord. Mesoderm is a part of endoderm.
4. Remaining endoderm forms from megameres.
5. At the end of gatrulation, blastopore contracts and the megameres close this pore.
6. These megameres look like a plug and so this is termed as Yolk plug stage. It is formed at the end of gastrulation.