What is the primary role of the immune system?

The primary role of the immune system is to protect the body against pathogens. This encompasses a range of biological structures, cells, and processes that detect and neutralize harmful invaders such as bacteria, viruses, parasites, and fungi. The immune system functions through various mechanisms, including the innate immune response, which provides immediate, non-specific defense, and the adaptive immune response, which develops specific defenses against particular pathogens over time.

This system is crucial for maintaining health, as it not only fights off infections but also helps to identify and destroy cells that might become cancerous. By recognizing and responding to foreign substances, the immune system plays a vital role in preserving the integrity of the body's internal environment and ensuring that it can operate efficiently and effectively against various threats.