Final answer:
The absorbing structure in the uterus during embryo development is the placenta, providing vital nutrients and oxygen. Trophoblast cells of the blastocyst develop into the placenta. The embryo then undergoes folding, cell differentiation, and organogenesis to form a viable fetus.
Step-by-step explanation:
The absorbing structure in the uterus during the development of an embryo is the placenta. This vital organ forms during the embryonic stage of development and connects the developing embryo to the uterine wall. It provides the embryo with oxygen and nutrients through the blood vessels that grow from the embryo via the umbilical cord, and also allows for the removal of waste products.
After the initial division and travel of the zygote, it reaches the uterus as a morula and forms into a blastocyst. The trophoblasts, which are the outer cells of the blastocyst, will further develop into the chorionic sac and the fetal portion of the placenta. As pregnancy advances, the placenta becomes an essential component in providing life support to the growing fetus.
Embryonic folding is another key process, forming the primitive gut and enveloping a portion of the yolk sac which protrudes with the umbilical cord. As development proceeds, embryonic cells differentiate into three primary germ layers and contribute to organogenesis, laying down the foundation for all future organ systems of the fetus during gestation, which culminates in the birth of a newborn.