The body’s innate defenses against infection include memory cells.
True
False
The correct answer and explanation is:
Correct Answer: False
The body’s innate defenses against infection do not include memory cells. Memory cells are a feature of the adaptive immune system, not the innate immune system.
The immune system is divided into two main branches: innate immunity and adaptive immunity. Innate immunity is the body’s first line of defense. It responds quickly and non-specifically to a wide range of pathogens. Components of innate immunity include physical barriers like the skin and mucous membranes, chemical barriers like stomach acid, and immune cells like neutrophils, macrophages, natural killer cells, and dendritic cells. These defenses are present from birth and do not improve or change based on previous exposure to a pathogen.
In contrast, the adaptive immune system is more specific and slower to respond at first, but it has the ability to remember previous encounters with pathogens. This memory is established through the production of memory B cells and memory T cells. These cells “remember” specific antigens from pathogens and allow the immune system to respond more rapidly and effectively upon subsequent exposure. This is the principle behind how vaccines work: by introducing a harmless form of the pathogen, the body develops memory cells without causing illness.
Therefore, since memory cells are a hallmark of the adaptive immune system and not the innate immune system, the statement is false. The innate immune system provides immediate but generalized defense, while the adaptive immune system, which includes memory cells, tailors its response and improves with repeated exposure.