Question

Name the organ which connects the placenta to the embryo.

Answer 1

Hint: The placenta is known to be a temporary fetal organ that develops from the blastocyst after the implantation has taken place. The placenta is said to have evolved 150 to 200 million years ago and the role of the placenta is very important in humans.

Complete answer:
The placenta comprises an outer barrier protein known as syncytin that is found between the mother and the baby, it is known to have an RNA signature in its genome that led to the assumption that the placenta originated from an ancient retrovirus.

The organ that connects the placenta to the embryo is the umbilical cord that contains one umbilical vein and two umbilical arteries. The umbilical cord develops during the fifth week and serves to provide nutrients to the embryo. The umbilical cords enter inside the fetus through the abdomen, the umbilical vein then divides into two branches one which carries blood to the liver and the other carries blood to the heart. The two umbilical arteries, in turn, carry blood back to the placenta thus completing the circuit.

After birth both the umbilical vein and the umbilical artery closes up as a result of the reduction in temperature as well as vasoconstriction of the blood vessels due to smooth muscle contraction following which they are removed from the baby.

Thus the correct answer is Umbilical arteries.

Note: The umbilical cord is an important part of the developing embryo any abnormalities can cause serious problems which can affect both the mother and the baby. Few of the abnormalities include entanglement of the cord, single umbilical artery, umbilical cord prolapse, velamentous cord insertion and vasa praevia.