Although it contributes no cells to the embryo, this structure guides the formation of the primitive streak:
A)endoderm
B)mesoderm
C)ectoderm
D)neural crest
E)hypoblast

Question

Quizplus · Accepted Answer

The hypoblast is a layer of cells that forms during gastrulation and contributes to the formation of the yolk sac. It does not contribute any cells to the embryo, but it does give rise to some important structures, including the endoderm and the extraembryonic mesoderm. The hypoblast also plays a key role in guiding the formation of the primitive streak, which is the first visible sign of gastrulation. As cells move through the primitive streak and begin to differentiate into the three germ layers (endoderm, mesoderm, and ectoderm), the hypoblast helps to establish the correct orientation and positioning of these layers.

Although It Contributes No Cells to the Embryo, This Structure