Binary (secondary) exposure to an antigen results in sudden increase in ?

Ans. is d i.e., IgM This is a tricky one. Though the predominant antibody in secondary response is IgG, initially there is an immediate brief period dring which IgM is produced before IgG. It must be noted that both IgM and IgG are produced during primary as well as secondary response i) IgM is the predominant antibody in primary response. ii) IgG is the predominant antibody in secondary response. iii) IgM is the first antibody produced in both primary as well as secondary response.