A very early stage of embryonic development. About 4-5 days after conception the embryo consists of a ring of cells with fluid in the center and a clump of cells at one end with a thinner layer of cells at the other end.
A very early stage of embryonic development. About 4-5 days after conception the embryo consists of a ring of cells with fluid in the center and a clump of cells at one end with a thinner layer of cells at the other end.