Cornea transplant in humans is almost never rejected.This is because

Options

A. Its technique is very simple
B. The preservation of cornea is very simple
C. Cornea has no relation with blood circulation and immunization
D. Cornea is available easily

Answer

### Step-by-Step Solution:

1. **Understanding Cornea Transplantation**:
- A cornea transplant involves replacing a damaged or diseased cornea with a healthy one from a donor. The cornea is the transparent front part of the eye that covers the iris and pupil.

2. **Blood Supply and Immune Response**:
- The cornea is unique in that it does not have a direct blood supply. Instead, it receives oxygen directly from the air and nutrients from the tear fluid. This lack of blood vessels means that the immune system has less opportunity to recognize the transplanted tissue as foreign.

3. **Immunological Privilege**:
- Tissues that do not have a blood supply, like the cornea, are often referred to as being in a state of "immunological privilege." This means that they can tolerate the presence of foreign material without triggering a strong immune response.

4. **Healing Capacity**:
- The cornea has a high healing capacity. If the cornea is injured or damaged, it can heal quickly, which also aids in the success of transplants.

5. **Conclusion**:
- Because the cornea lacks blood vessels, it is less likely to be rejected by the recipient's immune system. This is the primary reason why cornea transplants are almost never rejected.

### Final Answer:
Cornea transplant in humans is almost never rejected because the cornea has no blood supply, which means it does not trigger a strong immune response, allowing for successful transplantation.

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