Question

Which blood vessel carries deoxygenated blood back to placenta

• A. Umbilical Artery
• B. Umbilical vein
• C. Uterine artery
• D. Descending aorta

Answer 1

The Correct Option is A

In fetal circulation, the direction of blood flow in the umbilical vessels is:

$\text{Umbilical Artery}$ -- carries $\text{deoxygenated}$ fetal blood from fetus $\rightarrow$ placenta
$\text{Umbilical Vein}$ -- carries $\text{oxygenated}$ blood from placenta $\rightarrow$ fetus

Memory trick: DAVE -- Deoxygenated blood is carried Away (in arteries) from the fetus to the placenta; oxygenated blood returns Via the umbilical vEin.

Key fact: The umbilical cord has 2 arteries and 1 vein. The two umbilical arteries are branches of the internal iliac arteries and carry waste-laden, deoxygenated blood toward the placenta for replenishment.

Why not other options?
- Umbilical vein: brings oxygenated blood back to fetus (opposite direction)
- Uterine artery: maternal vessel, not in umbilical cord
- Descending aorta: fetal systemic circulation, not a direct placental vessel

\[\boxed{\text{Umbilical Artery}}\]