Question

question 42 (0.5 points)
which activates the classical complement cascade?
binding of antigen-antibody complexes to c1
direct interaction of c3 with bacterial cell membranes
activation of c3b by factor d
binding of mannose-binding lectin (mbl) to bacterial surfaces

Explanation:

The classical complement cascade is activated by the binding of antigen - antibody (immune) complexes to the C1 component of the complement system. The direct interaction of C3 with bacterial cell membranes is part of the alternative pathway. Activation of C3b by factor D is also related to the alternative pathway. Binding of mannose - binding lectin (MBL) to bacterial surfaces activates the lectin pathway. So the correct option is the one about the binding of antigen - antibody complexes to C1.

Answer:

A. Binding of antigen - antibody complexes to C1