Final answer:
C5a plays a crucial role in the immune system as a chemotactic agent and anaphylatoxin, attracting and activating immune cells to fight against pathogens and maintain homeostasis.
Step-by-step explanation:
The role of C5a in the immune system is as a chemotactic agent and anaphylatoxin. C5a is a fragment of the complement system that is released during complement activation. It attracts and activates immune cells, such as neutrophils, macrophages, and mast cells, to the site of infection or inflammation.
It also promotes inflammation by increasing blood vessel permeability. C5a plays a crucial role in the innate immune response by recruiting and activating various immune cells to fight against pathogens and maintain homeostasis.