Anatomy and Physiology II Practice Test

What type of immunity is provided to an infant through the mother's breast milk?

1. Natural active immunity

2. Natural passive immunity

3. Artificial active immunity

4. Artificial passive immunity

The correct answer is: Natural passive immunity

The type of immunity provided to an infant through the mother's breast milk is natural passive immunity. This immunity occurs when antibodies are transferred from one individual to another, providing immediate protection without the need for the recipient's immune system to produce the antibodies itself. In the case of breast milk, particularly colostrum, the first milk that a mother produces after giving birth, there are high concentrations of immunoglobulins, primarily immunoglobulin A (IgA). These antibodies play a crucial role in protecting the infant against pathogens by coating the lining of the gastrointestinal tract and preventing these pathogens from entering the bloodstream. Natural passive immunity is generally temporary, lasting only as long as the antibodies are present in the infant's system. Unlike active immunity, which involves the body generating a response and developing memory cells against specific pathogens, passive immunity does not stimulate the infant's immune response and does not result in long-term immunity once the antibodies degrade. Understanding this distinction helps highlight the unique role that breast milk plays in early life, equipping infants with vital antibodies that bolster their immune system during a critical period of development.