Blood flowing through umbilical cord of mammalian embryo is

Options

A. 100% foetal
B. 100% maternal
C. 50% maternal and 50% foetal
D. 75% maternal and 25% foetal

Answer

**Step-by-Step Solution:**

1. **Understanding the Umbilical Cord**: The umbilical cord is a vital structure that connects the developing embryo (fetus) to the placenta in mammals. It is composed of one vein and two arteries.

2. **Function of the Umbilical Cord**: The umbilical cord serves as a conduit for blood flow between the mother and the fetus. The two umbilical arteries carry deoxygenated blood away from the fetus to the placenta, while the umbilical vein carries oxygenated blood from the placenta back to the fetus.

3. **Blood Composition**: The blood that flows through the umbilical cord is primarily fetal blood. The umbilical vein carries blood that is rich in oxygen and nutrients, which is essential for the growth and development of the fetus.

4. **Clarifying Blood Types**: The blood in the umbilical cord is 100% fetal blood. This means that the blood circulating through the umbilical cord is entirely derived from the fetus and not mixed with maternal blood.

5. **Conclusion**: Based on the functions and composition of the blood in the umbilical cord, the correct answer to the question is that the blood flowing through the umbilical cord of a mammalian embryo is 100% fetal blood.

**Final Answer**: The blood flowing through the umbilical cord of a mammalian embryo is 100% fetal blood.

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