Describe the flow of oxygenated blood from the placenta to the fetus\' systemic circulation and deoxygenated blood from the fetus to the placenta. Be sure to include all five structures that allow for fetal circulation to take place effectively. Solution Placenta receives blood from two systems: a uteroplacental system that delivers maternal blood to the placenta; and the fetoplacental system that receives from the fetus. The umbilical vein carries blood from the placenta to the fetus. A majority of it enters liver and 1/3rd is diverted to ductus venosus and carried to inferior vena cava. In liver proper, the blood enters from its inferior border. A branch of the umbilical vein joins the portal vein. The blood is then supplied to the right atrium of the heart. The heart has an opening connecting left and right atrium called foramen ovale. Due to this opening, the blood bypasses the pulmonary circulation and is directly circulated to the body of the fetus, via the aorta. Some of the blood moves to the placenta through iliac and then umbilical arteries into the mother\'s blood circulation for the exchange of gasses and removal of waste products. A part of the blood that enters the atrium of the fetus enters left ventricle and is pumped to the pulmonary artery The pulmonary artery of the fetus is connected to the aorta via ductus atriosus and thus the blood enters aorta and escapes from entering the lungs. The blood in aorta takes the same route as described earlier..

1. Describe the flow of oxygenated blood from the placenta to the fetus' systemic circulation and
deoxygenated blood from the fetus to the placenta. Be sure to include all five structures that
allow for fetal circulation to take place effectively.
Solution
Placenta receives blood from two systems: a uteroplacental system that delivers maternal blood
to the placenta; and the fetoplacental system that receives from the fetus.
The umbilical vein carries blood from the placenta to the fetus. A majority of it enters liver and
1/3rd is diverted to ductus venosus and carried to inferior vena cava. In liver proper, the blood
enters from its inferior border. A branch of the umbilical vein joins the portal vein. The blood is
then supplied to the right atrium of the heart. The heart has an opening connecting left and right
atrium called foramen ovale. Due to this opening, the blood bypasses the pulmonary circulation
and is directly circulated to the body of the fetus, via the aorta. Some of the blood moves to the
placenta through iliac and then umbilical arteries into the mother's blood circulation for the
exchange of gasses and removal of waste products.
A part of the blood that enters the atrium of the fetus enters left ventricle and is pumped to the
pulmonary artery The pulmonary artery of the fetus is connected to the aorta via ductus atriosus
and thus the blood enters aorta and escapes from entering the lungs. The blood in aorta takes the
same route as described earlier.