What is the primary function of lymphatic capillaries?

The primary function of lymphatic capillaries is to allow large amounts of tissue fluid and debris to enter the lymphatic system. These tiny, thin-walled vessels are crucial for collecting excess interstitial fluid, proteins, and waste products from the spaces between cells in tissues.

When tissues experience inflammation or increased permeability, lymphatic capillaries can absorb not just fluid but also larger molecules and particulate matter such as pathogens, dead cells, and other debris. This absorption helps maintain fluid balance in the body and plays a vital role in the immune response by transporting collected debris to lymph nodes, where it can be processed and filtered.

In contrast, transporting oxygenated blood to tissues is a function of the circulatory system's arteries. Filtering pathogens from the bloodstream is a role attributed mainly to the spleen and lymph nodes rather than the lymphatic capillaries themselves. Regulating pH balance is primarily managed through respiratory and renal processes rather than through the lymphatic system. Hence, the correct interpretation of the role of lymphatic capillaries highlights their importance in fluid balance and immune function.