And then the C One protein can go on to activate the C two and C four. And that forms a complex known as C four B, C two B complex. And then that activates C Three, which in turn activates C five and that produces our membrane attack complex mac mac. And that basically initiates many different types of mechanisms that eventually protect our body from different types of pathogenic agents and antigens. Now, what about the alternative pathway? Well, unlike the classical pathway, which needs the presence of our antibody antigen complex to initiate, the alternative pathway can be triggered even in the absence of the antibody antigen complex.