Which of the folloing hormones is used in transplantation surgery to suppess immunity, and thus, chances of organ rejection by recipient's body is decreased ?

Options

A. Thyroxine
B. Cortisol
C. Aldosterone
D. Steroid hormone

Answer

**Step-by-Step Solution:**

1. **Understanding the Context of Transplantation Surgery:**
- In transplantation surgery, an organ from a donor is transplanted into a recipient. The recipient's immune system may recognize the donor organ as foreign and attempt to reject it.

2. **Role of the Immune System:**
- The immune system is designed to protect the body from foreign substances, including bacteria, viruses, and transplanted organs. It can mount a response against anything it identifies as non-self.

3. **Need for Immunosuppression:**
- To prevent the rejection of the transplanted organ, it is necessary to suppress the immune response of the recipient. This is where specific hormones or medications come into play.

4. **Identifying the Correct Hormone:**
- Among the options provided (thyroxine, cortisol, aldosterone, and steroid hormone), we need to identify which hormone is used to suppress immunity during transplantation.
- Cortisol is a hormone produced by the adrenal glands and is known for its immunosuppressive properties.

5. **Conclusion:**
- The hormone that is used in transplantation surgery to suppress immunity and decrease the chances of organ rejection is **cortisol**.

**Final Answer:**
Cortisol is the hormone used in transplantation surgery to suppress immunity and decrease the chances of organ rejection.

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