Question

Deoxygenated blood is not seen in?

• A. Pulmonary artery
• B. Umbilical artery
• C. Umbilical vein
• D. Right heart

Hint:

The umbilical vein is the exception: it carries oxygenated blood from the placenta to the fetus.

Answer 1

The Correct Option is C

Step 1: Recall the general rule and its exceptions. Most arteries carry oxygenated blood and most veins carry deoxygenated blood, but the pulmonary and umbilical vessels are the classic exceptions.
Step 2: Analyse each vessel. The pulmonary artery carries deoxygenated blood from the right ventricle to the lungs. The right heart (right atrium and right ventricle) receives systemic venous return and therefore contains deoxygenated blood.
Step 3: Analyse the fetal umbilical vessels. The umbilical arteries carry deoxygenated blood from the fetus to the placenta. The umbilical vein, in contrast, carries OXYGENATED blood from the placenta back to the fetus.
Step 4: Trace the fetal pathway to confirm. Oxygenated blood travels from the placenta through the umbilical vein, then via the ductus venosus to the inferior vena cava and right atrium, where it is preferentially shunted across the foramen ovale. Thus the umbilical vein is the one vessel in the list that does not carry deoxygenated blood.
Conclusion: Deoxygenated blood is not seen in the umbilical vein, so the correct answer is option 3.