AP BIOLOGY

Detailed explanation-1: -During the last 3 months of pregnancy, antibodies from mothers are passed to their unborn babies through the placenta. This type of immunity is called passive immunity because the baby has been given antibodies rather than making them itself.

Detailed explanation-2: -A specific type of antibody found in breastmilk, IgA, protects infants from infections. When breast milk coats the baby’s oral mucosa, nasal cavity, Eustachian tubes, and GI tract, the IgA binds to bacteria and viruses at that surface preventing them from entering the baby’s system.

Detailed explanation-3: -Results: Human milk protects against infections in the breastfed offspring mainly via the secretory IgA antibodies, but also most likely via several other factors like the bactericidal lactoferrin.

Detailed explanation-4: -IgG Antibodies in Breast Milk Help Shape Infants’ Gut Bacteria and Immunity. Researchers have known for some time that maternal breast milk provides critical nutrients for newborns, and antibodies from mothers vaccinated against a specific disease-causing bacterium or virus can be transferred via breast milk to babies.

Detailed explanation-5: -A large part of immunoglobulins excreted in milk are IgA that protect mainly against enteric infections. The specificity of maternal milk IgA is driven by an entero-mammary cell circulation. Human milk also contains anti-idiotypic antibodies capable of enhancing infant antibody response.