Hematopoesis

Question 1

Functions of the yolk sac in mammals?

Answer 1

The yolk sac is lined with extraembryonic endoderm and mesoderm.

1. The mesoderm gives rise to Primordial Germ Cells (PGC) that form spermatogonia and oogonia.
2. Mesodermal cells become organised into blood islands to supply oxygen to the embryo.