What is the primary function of the immune system?

The primary function of the immune system is to protect against pathogens. This involves a complex network of cells, tissues, and organs that work together to identify and eliminate harmful organisms such as bacteria, viruses, fungi, and parasites. The immune system plays a vital role in recognizing foreign substances and mounting an appropriate response, which can include the production of antibodies, activation of white blood cells, and more.

This protective function is essential for maintaining health and preventing infections, making it a key focus within the field of health and medicine. Understanding the role of the immune system helps to appreciate how the body defends itself and the importance of vaccinations and other health practices that bolster immune response. Other options, such as digestion, temperature regulation, and hormone production, relate to different body systems and functions that do not directly pertain to the immunity process.