A pediatrician explains to a medical student that a specific fetal shunt carries the most oxygenated blood directly to the coronary and cerebral circulations. Which structure is responsible for this preferential streaming?
- A Ductus venosus ✓
- B Ductus arteriosus
- C Umbilical artery
- D Foramen ovale
Correct answer: A. Ductus venosus
Explanation
The ductus venosus shunts highly oxygenated blood from the umbilical vein past the liver directly into the inferior vena cava. This blood is then directed across the foramen ovale to the left atrium, preferentially supplying the heart and brain. The ductus arteriosus shunts deoxygenated blood from the pulmonary artery to the aorta, bypassing the lungs.
Reference: Langman's Medical Embryology, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.