The placenta's an organ unique to mammals that connects the developing fetus to the uterine wall. The placenta supplies the fetus with oxygen and food, and allows fetal waste to be disposed of via the maternal kidneys. The word placenta comes from the Latin for cake, from Greek plakóenta/plakoúnta, accusative of plakóeis/plakoús - πλακόεις, πλακούς, "flat, slab-like", referring to its round, flat appe… (More on Placenta)