What organ leads to the umbilical cord in a fetal pig?
The umbilical cord leads to the mouth in a fetal pig. The function of this cord is to transport nutrients from the mother to the fetus.
The fetal circulation is the circulatory system of a human fetus, often encompassing the entire fetoplacental circulation that also includes the umbilical cord and the blood vessels within the placenta that carry fetal blood. The fetal circulation works differently from that of born humans, mainly because the lungs are not in use: the fetus obtains oxygen and nutrients from the mother through the placenta and the umbilical cord.
No, only mammals which develop inside the mother's womb depend on a placenta for their growth, and therefore have an umbilical cord. (There is no umbilical cord involved in the development of those few mammals who lay eggs or whose babies develop in the mother's pouch.) Since birds are hatched from eggs, no placenta-umbilical cord mechanism is involved. Most of a fetal bird's development takes place outside its mother's body, in the egg.
The umbilical cord connects the navel of a fetus with the placenta. When the baby is born the umbilical cord is cut. The belly button is the location where the umbilical cord connected to the placenta. Umbilical cord is located at the umbilicus of the new born. The other end is attached to the placenta. Fetus gets the nourishment from the mother via umbilical cord.