The layer of the cell that forms the outer layer of the blastocyst is called ___________

Options

A. Amnion
B. Allantois
C. Placenta
D. Trophoblast

Answer

**Step-by-Step Solution:**

1. **Understanding the Blastocyst Structure**: The blastocyst is an early stage of embryonic development that consists of a mass of cells. It has an outer layer and an inner cavity.

2. **Identifying the Layers**: The outer layer of the blastocyst is crucial for its function. It is responsible for the implantation of the blastocyst into the uterine wall.

3. **Recognizing the Specific Layer**: The outer layer of the blastocyst is made up of a specific type of cells. These cells are known for their role in attaching the blastocyst to the uterus.

4. **Naming the Layer**: The outer layer of the blastocyst is called the **trophoblast**. This layer plays a vital role in the implantation process and helps in the formation of the placenta.

5. **Conclusion**: Thus, the layer of the cell that forms the outer layer of the blastocyst is called the **trophoblast**.

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