Question

A detective found some body fluids on a victim's clothes. the body fluids were sent to the crime lab for analysis. on the basis of the antibody analysis, could the crime lab determine whether the sample is blood plasma or semen? explain your answer.

Answer 1

IgA antibodies are found in body secretions such as tears, saliva, semen, vaginal secretions but not in blood plasma. Plasma contains IgM, IgG, IgD, and IgE antibodies. By testing for the presence or absence of IgA and IgG, the lab could determine whether the sample is blood plasma or semen.