EN
The immune system is, besides the nervous and hormonal systems, one of the three systems crucial for the balance (homeostasis) of the basic biological functions of the system (metabolism, growth, reproductiveness, immunity). The author uses a metaphor comparing the immune system to the resistance system of a company. In the article systems are also differentiated according to the criterion of peculiarity. They are as follows: the subsystem of exterial barriers, the subsystem of non-peculiar resistance, the subsystem of blurred peculiarity, the subsystem of targeted defence. The notion of the disturbance factor nas been defined and described as well