What is one of the primary roles of the lymphatic system?

The primary role of the lymphatic system is to filter and return fluid to the bloodstream. The lymphatic system consists of a network of vessels, nodes, and organs that transport lymph, a clear fluid that contains white blood cells, nutrients, and waste products. As blood circulates through the body, some of the fluid leaks out of the capillaries into the surrounding tissues. The lymphatic system collects this excess fluid, filters it through lymph nodes (where it can be cleared of pathogens), and eventually returns it to the bloodstream. This process is essential for maintaining fluid balance in the body, supporting the immune system, and facilitating nutrient transport.

While the other options represent important functions in the body—digestion, hormone production, and temperature regulation—they are not primary roles of the lymphatic system. Each of those functions is managed by different systems within the body, such as the digestive system, endocrine system, and thermoregulatory processes. Understanding the distinct role of the lymphatic system highlights its critical importance in overall health and immune function.