2. Describe the sources of antibodies in humans from pre-birth to old age, including how our bodies change over time as we age.

Explanation:

More than 1600 genes are involved in innate and adaptive immune responses. These genes are of great importance for sustaining life in a hostile environment. Yet the immune system is relatively immature at birth and has to evolve during a life of exposure to multiple foreign challenges through childhood, via young and mature adulthood (including pregnancy), to the decline of old age