What is the main function of the immune system?

The main function of the immune system is to protect the body against pathogens, which are harmful microorganisms like bacteria, viruses, fungi, and parasites. It accomplishes this through a complex network of cells, tissues, and organs that work together to recognize and respond to these invaders. The immune system identifies foreign substances and mounts an appropriate response, including the production of antibodies, activation of immune cells, and the coordination of inflammatory responses.

This protective role is crucial for maintaining health and preventing infections and diseases. Without a properly functioning immune system, the body becomes vulnerable to infections and can struggle to recover from illnesses. Hence, the role of the immune system is distinct and separate from other bodily functions like digestion or hormone production, which are handled by different systems in the body.