During the embryonic stage, what forms on the uterine wall is the trophoblast. The trophoblast is the outer layer of cells that forms after fertilization of the egg and its implantation into the uterine wall. This structure plays a crucial role in the implantation of the embryo into the uterine lining and eventually develops into the placenta.
1. Trophoblast: This outer layer of cells is responsible for the initial attachment of the embryo to the uterine wall. It provides essential support for the developing embryo by helping to form the placenta, which is vital for the exchange of nutrients and waste between the mother and the fetus.
2. Placenta: As the embryo grows and develops, the trophoblast gives rise to the placenta. The placenta is an organ that connects the developing fetus to the uterine wall, allowing for the exchange of nutrients, oxygen, and waste products between the mother and the baby. It also produces hormones that support the pregnancy.
In summary, during the embryonic stage, the trophoblast forms on the uterine wall, eventually developing into the placenta, which is crucial for the growth and development of the fetus.
