Answer:
below the full answer
Step-by-step explanation:
The third line of defense, also known as the adaptive immune response, involves the activation of specific immune cells, such as T and B lymphocytes, to target and eliminate specific pathogens, such as Staphylococcus.
When a pathogen, such as Staphylococcus, enters the body, it is recognized by the innate immune system, which triggers the activation of T and B lymphocytes. T lymphocytes, also known as T cells, can be divided into two main subtypes: CD4+ T cells and CD8+ T cells. CD4+ T cells, also known as helper T cells, help to coordinate the immune response by releasing chemicals called cytokines that help to attract other immune cells to the site of infection. CD8+ T cells, also known as cytotoxic T cells, directly target and kill infected cells.
B lymphocytes, also known as B cells, produce and release antibodies that can specifically bind to and neutralize the pathogen. Once a B cell encounters a pathogen, it produces a large number of identical copies of itself, known as plasma cells, that produce the specific antibody that can neutralize the pathogen.
Both T and B cells also have memory cells that remember the pathogen, so that they can respond quickly if the same pathogen enters the body again in the future.
So in summary, the third line of defense involves the activation of specific immune cells, such as T and B lymphocytes, which target and eliminate specific pathogens like Staphylococcus by releasing chemicals and neutralizing the pathogen.