4. Difficulties often occur when tissues or organs are
transplanted from one person to another because the
(1) transplanted structures cannot produce new cells
(
2)
rate of mitosis differs between the two people
involved
(3) introduction of a foreign substance causes the
formation of antibodies
(4) two people often have the same blood type



Answer :

Final answer:

The rejection of transplanted organs is primarily due to the immune system's response to foreign tissues, particularly related to different MHC I molecules between donors and recipients.


Explanation:

Different MHC I molecules between donor and recipient cells can lead to rejection of a transplanted organ or tissue due to the recipient's immune system recognizing the donor tissue as foreign and triggering an immune response. This rejection process involves major histocompatibility complex markers MHC I and MHC II, specifically human leukocyte antigens (HLAs), playing a critical role.


Learn more about Transplant Rejection here:

https://brainly.com/question/21144644