question_answer 77)

  For an organ transplant, it is an advantage to have an identical twin. Why?

Answer:

                  For an organ transplant, it is an advantage to have an identical twin because the organ will have same surface markers and therefore, the recipient's immune system will not identify it as foreign and will not react against it. In case of different surface markers, the immune system starts a reaction, kills the foreign tissue or rejects it.