what is placenta?

The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother`s blood supply. Placentas are a defining characteristic of eutherian or "placental" mammals, but are also found in some non-mammals with varying levels of development.The word placenta comes from the Latin word for cake, from Greek plakóenta/plakoúnta,