Question

Describe the 3 lines of defense in the immune system, making sure to include if they're specific or non specific. Then identify how your body remembers pathogens and is able to gain immunity to them, as well as what is unique about the cells that do this.

Answer 1

The immune system has three lines of defense: 1) non-specific physical and chemical barriers, 2) non-specific immune responses, and 3) specific immune responses. The third line of defense involves highly specialized cells called lymphocytes, including B cells and T cells, which produce antibodies and directly attack infected cells. The body remembers pathogens through a process called immunological memory, maintained by memory cells that persist in the body and can quickly produce a specific immune response upon subsequent exposures to the same pathogen. Memory cells have a longer lifespan than other B and T cells, allowing for long-lasting immunity and the basis for many vaccines.