The immunoglobulin that crosses placental barrier is

Ans. b (IgG). (Ref: Jawetz's Medical Microbiology, 24th/Table 8-l;Obstetrics by Dutta, 4th/677)# Antigens of MCH have been shown to be well expressed in newborn, in the fetus and in embryo of 10th week.# IgG abs can cross placenta. IgGIgAIgMIgEIgDHeavy chain symbolgabedMolecular weight (x 1000)150170 or 4001900190150Serum concentration (mg/mL)7-180.8-40.4-2.5< 0.0005< 0.003Serum half-life (days)217722Activates complementYes (+)NoYes (++)NoNoPercentage of total immunoglobulins in serum80136< 1< 1Crosses placentaYesNoNoNono