Although it contributes no cells to the embryo, the formation of the primitive streak is guided by the structure known as the
A) endoderm.
B) mesoderm.
C) ectoderm.
D) neural crest.
E) hypoblast.

Question

Quizplus · Accepted Answer

The primitive streak's formation is guided by the hypoblast, which, although it does not contribute cells directly to the embryo, plays a crucial role in signaling pathways that organize the embryonic development.

Although It Contributes No Cells to the Embryo, the Formation