Question
What is placenta? Mention its role during pregnancy?
✓
Answer
Followed by fertilization, placenta is developed which serve to provide nutrition and oxygen to developing embryo from the mother's blood. It is a disc embedded in the uterine wall and contains villi on the embryo's side of the tissue while blood spaces surrounding the villi are present on mother’s side. The embryo is connected to the placenta by umbilical cord, a tube like structure.Placenta serves to fulfill all nutritional requirements of developing embryo by supplying food and oxygen from mother’s blood to the embryo. Waste products of developing embryo are removed by transferring them into the mother's blood through the placenta. Functions of placenta are facilitated by villi that provide large surface areas for passage of nutrition and oxygen to embryo from mother through blood.
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