The adaptive immune response, or third line of defense, is activated when the first and second lines of defense do not succeed in containing an infection. it is adaptive because the cells in this part of the immune system are capable of responding to specific pathogens. another important feature of the third line is the ability of these cells to create memory cells. why are memory cells an important product of an immune response

Memory cells refer to a kind of white blood cell, which can react promptly when it encounters with a microbe for the second time. They generate the right antibody for the specific microbe and destruct it before one feels unwell. This is illustrated as being immune to a disorder.

Thus, the memory cells are an essential product of an immune response, as they permit successive immune reactions against the similar antigen to take place more robustly an more briskly.

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.