Step-by-step explanation:
The immune system is able to differentiate between pathogenic cells and normal cells of the body in a variety of ways. First, the cells of the immune system are able to recognize certain molecules on the surface of foreign cells that are not found on the body's own cells. These molecules, called antigens, can be proteins, carbohydrates, lipids, or nucleic acids. The immune system also has receptors that recognize these molecules, which allows them to identify and respond to foreign cells.
In addition, immune cells are able to recognize the shape and size of foreign cells, which is different from the shape and size of the body's own cells. The immune system also uses a process called phagocytosis, in which immune cells engulf and destroy foreign cells. Finally, the immune system can detect the presence of certain molecules, such as cytokines and chemokines, that are produced by foreign cells and can be used to identify and respond to them.
Overall, the immune system uses a variety of mechanisms to differentiate pathogenic cells from normal cells of the body. This helps the body recognize and respond to foreign invaders and prevents them from causing harm.