When a surgeon conducts a cardiac bypass operation by transplanting a piece of vein from a patient’s leg to the same patient’s heart, this is a(n) _________.


a. rejected graft
b. autograft
c. allograft
d. type IV hypersensitivity
e. cardiograft

Verified step by step guidance

1. Understand the types of grafts: An autograft is a transplant of tissue from one part of a person's body to another part of the same person's body.
2. Consider the context: The problem describes a scenario where a vein is transplanted from the patient's leg to their heart, indicating the tissue comes from the same individual.
3. Eliminate options that do not fit: A rejected graft implies the body has rejected the tissue, which is not the case here. An allograft involves tissue from a different individual of the same species, and type IV hypersensitivity is an immune response, not a type of graft.
4. Recognize the correct term: Since the tissue is transplanted within the same individual, it is an autograft.
5. Conclude with the correct choice: The correct answer is 'b. autograft' as it matches the definition and context provided.

Key Concepts

Autograft

An autograft is a type of graft where tissue is transplanted from one site to another within the same individual. This procedure minimizes the risk of rejection since the tissue is genetically identical to the recipient's own cells. In the context of the question, the surgeon is using a vein from the patient's leg to repair the heart, making it an autograft.

Graft Rejection

Graft rejection occurs when the recipient's immune system recognizes the transplanted tissue as foreign and mounts an immune response against it. This is more common in allografts, where tissue is taken from a different individual. Understanding graft rejection is crucial for differentiating between types of grafts and their compatibility.

Allograft

An allograft is a transplant of tissue from one individual to another of the same species but with different genetic makeup. This type of graft carries a higher risk of rejection compared to autografts, as the recipient's immune system may identify the foreign tissue as a threat. Recognizing the differences between autografts and allografts is essential for understanding transplant procedures.