Human placenta is derived from

Options

A. Chorion
B. Allantois
C. Amnion
D. Allantois and chorion

Answer

**Step-by-Step Solution:**

1. **Understanding the Human Placenta**: The human placenta is a vital organ that forms during pregnancy and is responsible for nutrient and waste exchange between the mother and the developing fetus.

2. **Identifying the Layers**: The placenta is derived from extra-embryonic layers that develop alongside the embryo. The key layers involved in the formation of the placenta are the chorion, allantois, yolk sac, and amnion.

3. **Role of Each Layer**:
- **Allantois**: This layer is primarily involved in waste exchange and is sometimes referred to as the 'kidney' of the embryo.
- **Yolk Sac**: This structure provides initial nutrition to the embryo before the placenta is fully functional.
- **Amnion**: This layer surrounds the embryo and contains amniotic fluid, providing cushioning and protection from external shocks.
- **Chorion**: This is the outermost layer that forms the placenta. It is responsible for the attachment to the uterine wall and contains chorionic villi that facilitate nutrient and gas exchange between the mother and fetus.

4. **Conclusion**: The human placenta is primarily derived from the chorion, which is the outer extra-embryonic membrane that interacts with the maternal tissues to form the placenta.

5. **Final Answer**: Therefore, the correct answer is that the human placenta is derived from the chorion.

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