Infection and Immune System
The immune system is classified into two types, innate immunity and adaptive, which is acquired immunity. Some differences are present between the two divisions, but some cell functions and components are common. All alive substances are subject to attack from disease-causing mediators. The process of defence gets more sophisticated as organisms become more complex. Almost all multicellular animals have devoted cells or tissues to deal with infection. Jointly, these protections are known as the immune system. The main portions of the immune system are: the natural barriers (skin, mucous membranes, etc.), nonspecific cells (phagocytes, natural killer cells, etc.), and nonspecific molecules (complement, interferons, etc.). There are many factors, such as age, general health, nutrition, and genetic makeup of any human host, affect how the immune system responds to microorganisms.