The |umbilical cord| is the communicating channel between the |placenta| and the |fetus|. It sends waste products from the |fetus| to the |placenta| and returns the ~blood~ from the |placenta| to the |fetus|. At birth the arteries in the |umbilical cord| constrict and close, stopping the ~blood~ flow to the |placenta|. Soon after the birth the |umbilical cord| is cut short and securely clamped.
