Question

Which immunoglobulin comprises approximately 70% of serum antibodies and is capable of crossing the placenta?

Options

• IgA

• IgE

• IgM

• IgG

Answer 1

IgG is the most abundant immunoglobulin, comprising approximately 70% of serum. Its key function includes crossing the placenta to provide passive immunity to the foetus, protecting the developing baby before birth and during early infancy.