Question

C1 component of the classical complement pathway is made up of

Answer 1

Activation of complements by antigen-associated antibody. In the classical pathway, C1 binds with its C1q subunits to Fc fragments (made of CH2 region) of IgG or IgM, which has formed a complex with antigens. C4b and C3b are also able to bind to antigen-associated IgG or IgM, to its Fc portion.