Answered

Follow the dorsal aorta into the abdominal cavity to the umbilical artery branches. these branches pass through the umbilical cord to the placenta. would blood in these branches be high or low in oxygen?

Answer :

I believe that the blood in these branches are low in oxygen. Umbilical cord is the lifeline that attaches the placenta to the fetus. It is not directly connected to the mother's circulatory system but instead joins the placenta which transfers materials to and from the mother's blood without allowing direct mixing. The umbilical cord contains one vein (the umbilical vein) and two arteries (the umbilical arteries). The umbilical vein carries oxygenated blood, nutrient rich blood from the placenta to the fetus, and the umbilical arteries carry deoxygenated, nutrient depleted blood from the fetus to the placenta.