AIIMS 2005 Zoology Organ Transplantation Assertion Reason Question

Explanation of the Question

The question presents an assertion and a reason related to organ transplantation and the immune response. To analyze the correctness of both statements and their relationship, we need to explore the concepts involved.

Assertion:

Organ transplantation patients are given immunosuppressive drugs.

This statement is true. Organ transplantation involves transferring an organ from one body (donor) to another (recipient). The recipient's immune system recognizes the transplanted organ as foreign because it contains different antigens compared to the recipient's own tissues. To prevent the immune system from attacking the transplanted organ, patients are prescribed immunosuppressive drugs.

Reason:

Transplanted tissue has antigens which stimulate the specific immune response of the recipient.

This statement is also true. Transplanted tissues express specific proteins, known as antigens, that are not present in the recipient's body. When these foreign antigens are detected, they trigger the recipient's immune system to mount a response, which can lead to rejection of the transplant. This immune response involves the activation of T-cells and the production of antibodies, which are part of the specific (adaptive) immune response.

Conclusion on Correct Answer

Since both the assertion and the reason are true, and the reason correctly explains why immunosuppressive drugs are necessary (the presence of foreign antigens stimulates an immune response), the correct answer is:

A) If both Assertion & Reason are true and the reason is the correct explanation of the assertion.

Clarification of Incorrect Options

• Option B: This would be correct if both statements were true, but the reason did not explain the assertion. However, the reason does explain the assertion, so this option is incorrect.

• Option C: This would imply that the assertion is true while the reason is false. Since both statements are true, this option is incorrect.

• Option D: This option states that both the assertion and the reason are false. Since we have established that both are true, this option is also incorrect.

Summary

In summary, the relationship between the assertion and the reason is direct: the presence of foreign antigens in transplanted tissues indeed necessitates the administration of immunosuppressive drugs to prevent rejection. Therefore, the correct choice is A.

Understanding this relationship is crucial for students preparing for exams like NEET and JEE, as it highlights the interplay between the immune system and organ transplantation.