Describe how the immune system protects the body from the threat of disease. (minimum 5 sentences per paragraph)

The immune system is consist of a complex network of cells and organs that protect the body from infection. The lymph nodes are the part of the immune system. The basic function of the immune system is to keep germs out of the body and if any germ or bacteria get in it quickly destroy it. The white blood cells that are lymphocytes are the cells that fight against the bacterial cell if any infection occurs.

While in various species, the immune system can be organized into subsystems, example the natural immune system compared to the adaptive humoral immunity and this compared with cell-mediated immunity. Inside the living organism, the blood-brain barrier, blood-cerebrospinal fluid barrier, and comparable fluid–brain blocks classify the peripheral immune system from the neuroimmune system, which preserves the brain.

Pathogens can immediately develop and modify, and whereby it bypass exposure and stabilizes by the immune system. Despite it multiple resistance mechanisms within the area that have also emerged to identify and compensate pathogens.

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