Final answer:
The complement system consists of the classical and alternative pathways; it remains operational despite some proteins not binding, due to the cascade nature of the activation sequence.
Step-by-step explanation:
The complement system is an intricate array of proteins essential to the immune response, featuring a cascade mechanism that targets and destroys invading pathogens. The pathways involved in the complement system include the classical pathway, which is activated by antibodies bound to pathogens, and the alternative pathway, which does not require antibody activation but instead involves the spontaneous cleavage of complement protein C3. The lectin pathway, similar to the classical pathway, is activated by the binding of a mannose-binding lectin to a pathogen. It is not discussed here in the context of genetic mutation impacts.
The complement system can remain functional even when some of the proteins are unable to bind due to its cascading nature; not all proteins need to directly bind antibodies or pathogens to activate the next protein in the sequence.