Question

Complement Cascade (3 pathways, in order of activation timewise) ?

Answer 1

The complement cascade consists of three pathways: the classical pathway, the alternative pathway, and the lectin pathway. Each pathway is activated in a specific order and has its own method of activation. The classical pathway requires the presence of antibodies, while the alternative pathway is spontaneously activated by the breakdown of C3, and the lectin pathway is activated by lectins binding to pathogens.

Step-by-step explanation:

The complement cascade is a series of reactions in the immune system that helps to destroy pathogens. There are three pathways in the complement cascade: the classical pathway, the alternative pathway, and the lectin pathway. The pathways are activated in a specific order and each pathway has its own method of activation.

1. The classical pathway is activated when C1 reacts with antibodies that have bound to an antigen. This pathway is used during adaptive immune responses.
2. The alternative pathway does not involve antibody activation. Instead, it is spontaneously activated by the breakdown of C3. This pathway is important for innate immunity.
3. The lectin pathway is activated when lectins bind to carbohydrates on the surface of pathogens. This pathway is also part of innate immunity.