What is the main function of the immune system?

The primary function of the immune system is to protect the body against infections and diseases. This complex network of cells, tissues, and organs works together to identify and eliminate pathogens such as viruses, bacteria, and parasites. The immune system also plays a crucial role in recognizing and destroying cancerous cells, making it essential for maintaining overall health.

Components of the immune system include white blood cells, such as lymphocytes and phagocytes, which are key players in detecting foreign invaders. The immune response can be innate, providing immediate defense mechanisms, or adaptive, involving a slower but more targeted approach that develops memory against specific pathogens. This ability to remember previous encounters with pathogens is what allows the body to mount a quicker and more effective response upon subsequent exposures.

In contrast, the other choices involve functions that are not related to the immune system. Producing energy, assisting with digestion, and storing/releasing hormones pertain to other systems in the body, such as the digestive system and endocrine system. Understanding the dedicated role of the immune system helps to highlight its critical importance in health and disease management.