The term ductus venosus refers to ________.

The term ductus venosus refers to ________.

• A. A special fetal vessel that allows umbilical blood to bypass the liver
• B. An arterial structure that shunts blood to the lungs
• C. A vein that drains into the hepatic portal system
• D. A fetal structure that connects the right atrium to the left atrium

Answer: (A)

In fetal circulation, certain vessels shunt blood to prioritize delivery of oxygen to the heart and brain. The ductus venosus is a special fetal vessel that carries blood from the umbilical vein directly into the inferior vena cava, bypassing the liver. This arrangement lets well-oxygenated placental blood reach the heart quickly and efficiently. After birth, it closes and becomes the ligamentum venosum. The other structures mentioned are different shunts: one shunts blood from the arterial side toward the lungs, another drains portal blood into the liver, and another connects the right and left atria. So the description of a fetal vessel that allows umbilical blood to bypass the liver best matches the ductus venosus.

In fetal circulation, certain vessels shunt blood to prioritize delivery of oxygen to the heart and brain. The ductus venosus is a special fetal vessel that carries blood from the umbilical vein directly into the inferior vena cava, bypassing the liver. This arrangement lets well-oxygenated placental blood reach the heart quickly and efficiently. After birth, it closes and becomes the ligamentum venosum. The other structures mentioned are different shunts: one shunts blood from the arterial side toward the lungs, another drains portal blood into the liver, and another connects the right and left atria. So the description of a fetal vessel that allows umbilical blood to bypass the liver best matches the ductus venosus.