Question

LAB TOPIC 8 Vertebrate Anatomy II: The Circulatory and Respirato Discussion 1. What is the advantage of the circuit of fetal blood flow through the ductus arteriosus? 2. What is the advantage of fetal blood flow through the foramen ovale?

Answer 1

1. ductus arteriosus is a normal blood vessel that connects two major arteries - the aorta and pulmonary artery that carry blood away from the heart .

When the fetus is in the womb the baby gets oxygen directly from the the mother's placenta and the lungs are not used. so ductus arterious carries blood away from the lungs and sends it directly to the body . Mainly it bypass the lungs and liver and sends it directly to the body. At the time of birth and newborn breathes and begins to use the lungs the ductus is no longer needed and usually closes by itself during the first 2 days after birth.

2. foramen ovale : it is the hole in the interatrial septum to allow blood to flow from right atria to left atria.

as we all knew that fetus gets oxygen from the mother's placenta and the lungs are not used . so the foramen ovale allows the blood flow to bypass the lungs and allow oxgenated blood coming from the umblical vein via inferior vena cava to bypass the pulmonary circulation as the lungs are or no use at that time.