Final answer:
Hemolysis can occur when complement molecules attack and damage the plasma membranes of red blood cells after a recipient receives a blood transfusion with a mismatched blood type, which can lead to serious complications.
Step-by-step explanation:
Hemolysis can indeed occur after a mismatched blood transfusion because complement molecules act on and compromise the plasma membranes of the red blood cells (RBCs). When someone receives a transfusion with a blood type that does not match their own, the immune system recognizes the donor RBCs as foreign. This triggers a response wherein antibodies in the recipient's blood target the mismatched blood cells, leading to their agglutination (clumping). Furthermore, this response activates the classical complement cascade, a part of the immune system designed to destroy pathogens. This cascade can cause the formation of the complement membrane attack complex (MAC), which leads to the RBCs' lysis or bursting. The resulting damage and destruction of RBCs can cause serious health complications, such as hemoglobinuria, hypotension, or even shock, if not addressed promptly.