Final answer:
Fetal circulation involves an umbilical vein carrying oxygenated blood to the fetus and two umbilical arteries returning deoxygenated blood to the placenta.
Step-by-step explanation:
The fetal circulation process includes the exchange of oxygen-rich and oxygen-depleted blood through structures specifically evolved for the growing fetus. The umbilical vein carries oxygen-rich blood from the placenta to the fetus, while the two umbilical arteries carry oxygen-depleted blood from the fetus back to the placenta. This system allows for efficient gas exchange and nutrient delivery, bypassing immature fetal organs like the lungs and liver.