Difference Between Placenta and Umbilical Cord

Main Difference – Placenta vs Umbilical Cord

Placenta and umbilical cord are two components of the fetal-life support system of a developing fetus inside the uterus. Placenta absorbs nutrients and oxygen from mother’s bloodstream and transfers to the fetus via the umbilical cord. The main difference between placenta and umbilical cord is that placenta is a temporary organ which joins mother and the fetus whereas umbilical cord is the connecting link between developing fetus and the placenta of the mother.

This article looks at,

1. What is Placenta
      – Definition, Structure, Role
2. What is Umbilical Cord
      – Definition, Structure, Role
3. What is the difference between Placenta and Umbilical Cord

What is Placenta

Placenta is a temporary organ attached to the uterine wall, connecting the fetus to the mother. Both bloodstreams of mother and fetus are kept separately by the placenta while maintaining the connection between the two. Placenta is a round, flat organ, which is found in mammals and non-mammals with differential developments. Structurally, it is a hemochorial villous organ.

Placenta absorbs nutrients and oxygen from the mother’s bloodstream and eliminates the waste of the fetus to the mother’s blood. Umbilical cord is developed from the placenta and it carries substances between placenta and the fetus. Placenta serves as an immunological barrier for antigen attacks from maternal side as well. It is also an endocrine organ which produces many hormones like estrogen, progesterone and human placental lactogen and growth factors. These hormones and growth factors are involved in promoting and supporting the fetal growth. Chorionic villus is the functional unit of the placenta, containing fetal vascular endothelium, villous stromal and the layers of syncytiotrophoblasts/cytotrophoblasts. Vascular endothelium is involved in the maintenance of maternal placental circulation and fetoplacental circulation separately. Human placenta is shown in figure 1.

Figure 1: Human placenta

What is Umbilical Cord

Umbilical cord is the conduit between the developing fetus and the placenta. It runs through an opening of the stomach of the fetus. The average of the cord is about 50 cm long. Umbilical cord carries substances like nutrients, oxygen, gasses and waste products via placenta and the fetus. It is made up of one vein and two arteries. Vein is responsible for the transportation of oxygen and nutrients from the placenta to the fetus. Carbon dioxide along with other waste products are transported from fetus to the placenta via two arteries. The three blood vessels are protected by Wharton’s jelly. Wharton’s jelly is covered by a layer of membrane called amnion. The umbilical cord of a newly-born child is shown in figure 2.

Figure 2: Umbilical cord

Difference Between Placenta and Umbilical Cord

Definition

Placenta: Placenta is the organ which connects the developing fetus to the uterine wall.

Umbilical Cord: Umbilical cord is the conduit between developing embryo/fetus and the placenta.

Role

Placenta: Placenta allows the uptake of nutrients from mother’s bloodstream, gas exchange, waste elimination and thermal regulation of the fetus.

Umbilical Cord: Umbilical cord links placenta and fetus for the transformation of nutrients, gasses, and waste.

Origin

Placenta: Fetal placenta belongs to the fetus whereas maternal placenta belongs to the mother.

Umbilical Cord: Umbilical cord belongs to the fetus.

Conclusion

Placenta, umbilical cord and amniotic sac are the three components of the fetal-life support system of a developing fetus. The main difference between placenta and umbilical cord is their structure and role. Placenta is the organ which absorbs oxygen and nutrients from the mother’s blood. These nutrients and oxygen are transported through the umbilical cord to the fetus. Only maternal placenta bears the maternal origin. Fetal placenta and the umbilical cord bear fetal origin. Both placenta and umbilical cord are removed from the uterus after the child birth.

Reference:
1.Wang, Yuping. “Introduction.” Vascular Biology of the Placenta. U.S. National Library of Medicine, 01 Jan. 1970. Web. 03 May 2017.
2.”What is the umbilical cord? – Health questions.” NHS Choices. NHS, n.d. Web. 03 May 2017.
3.”Fetal Life-Support System: Placenta and Umbilical Cord.” American Pregnancy Association. N.p., 18 Apr. 2017. Web. 03 May 2017.

Image Courtesy:
1.”Placenta” By Gray38.png: User Magnus Manske on en.wikipediaderivative work: Amada44  talk to me – Gray38.png (Public Domain) via Commons Wikimedia
2. “Umbilical cord” (Copyrighted free use) via Commons Wikimedia