Cells of Rauber's are

Options

A. Trophoblast cells in contact with embryonal knob
B. Cells of inner cell mass
C. Cells present in the blastocoel
D. Uterine epithelial cells making contact with blastocyst

Answer

**Step-by-Step Solution:**

1. **Understanding Rauber's Cells**: Rauber's cells are a specific type of cells that are involved in early embryonic development. To answer the question, we need to identify what these cells are and their function.

2. **Identifying the Options**: The question provides three options:
- a. Tropoblast cell in contact with the embryonal knob
- b. The cells in the inner cell mass
- c. Cells present in the blastocyst and deuterium epithelium cell making contact with the blastocyst

3. **Analyzing the First Option**: The first option refers to tropoblast cells, which are the outer layer of cells in the blastocyst. These cells play a crucial role in the implantation of the embryo into the uterine wall. The term "embryonal knob" refers to the inner cell mass of the blastocyst, which eventually develops into the embryo.

4. **Analyzing the Second Option**: The second option mentions the cells in the inner cell mass. While the inner cell mass is important for embryo development, Rauber's cells are specifically associated with the tropoblast layer, not the inner cell mass itself.

5. **Analyzing the Third Option**: The third option discusses cells present in the blastocyst and their interaction with the deuterium epithelium. However, this description does not specifically identify Rauber's cells.

6. **Conclusion**: Based on the analysis, the correct answer is option (a) "tropoblast cell in contact with the embryonal knob." Rauber's cells are indeed a type of tropoblast cell that interacts with the inner cell mass (embryonal knob).

**Final Answer**: a. Tropoblast cell in contact with the embryonal knob

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