(C5b, C6, C7, C8, C9)
Membrane Attack Complex
CHAPTER 35, FIGURE 22 Initiation of action by complement occurs via three pathways: classical, alternative
(properdin), and lectin pathways.
CHAPTER 35, FIGURE 23 A cartoon representation of complement protein Cl. The Cl complex consists of
one Clq, two Clr, and two Cls molecules. The formation of the complex requires the presence of Ca2+. Clq contains
six polypeptide chains that form a globular structure that binds to antigen-antibody complexes at one end of each