Tubular vessels transport lymph back to the blood, ultimately replacing the volume lost during the formation of the interstitial fluid. Lymph also transports fats from the digestive system (beginning in the lacteals) to the blood via chylomicrons. Metastatic cancer cells can also be transported via lymph.

Lymph may pick up bacteria and transport them to lymph nodes, where the bacteria are destroyed. Lymph returns proteins and excess interstitial fluid to the bloodstream. However, as it flows through the lymph nodes it comes in contact with blood, and tends to accumulate more cells (particularly, lymphocytes) and proteins. Thus, lymph when formed is a watery clear liquid with the same composition as the interstitial fluid. Interstitial fluid forms at the arterial (coming from the heart) end of capillaries because of the higher pressure of blood compared to veins, and most of it returns to its venous ends and venules the rest (up to 10%) enters the lymph capillaries as lymph. Water and solutes can pass between the interstitial fluid and blood via diffusion across gaps in capillary walls called intercellular clefts thus, the blood and interstitial fluid are in dynamic equilibrium with each other. As the blood and the surrounding cells continually add and remove substances from the interstitial fluid, its composition continually changes. This exchange is not direct, but instead occurs through an intermediary called interstitial fluid, which occupies the spaces between cells. Starling forces are labelled: the hydrostatic pressure is higher proximally, driving fluid out oncotic forces are higher distally, pulling fluid in.īlood supplies nutrients and important metabolites to the cells of a tissue and collects back the waste products they produce, which requires exchange of respective constituents between the blood and tissue cells. The lymph formed in the human digestive system called chyle is rich in triglycerides (fat), and looks milky white because of its lipid content.ĭevelopment Formation of interstitial fluid from blood. Lymph that leaves a lymph node is richer in lymphocytes than blood plasma is. Lymph has a composition similar but not identical to that of blood plasma. Structure Human lymph, obtained after a thoracic duct injury

The word lymph is derived from the name of the ancient Roman deity of fresh water, Lympha.

Lymph also transports fats from the digestive system (beginning in the lacteals) to the blood via chylomicrons.īacteria may enter the lymph channels and be transported to lymph nodes, where the bacteria are destroyed. It is generally similar to blood plasma, which is the fluid component of blood. This lymphatic fluid is then transported via progressively larger lymphatic vessels through lymph nodes, where substances are removed by tissue lymphocytes and circulating lymphocytes are added to the fluid, before emptying ultimately into the right or the left subclavian vein, where it mixes with central venous blood.īecause it is derived from interstitial fluid, with which blood and surrounding cells continually exchange substances, lymph undergoes continual change in composition. At the origin of the fluid-return process, interstitial fluid-the fluid between the cells in all body tissues -enters the lymph capillaries. Lymph (from Latin, lympha, meaning 'water') is the fluid that flows through the lymphatic system, a system composed of lymph vessels (channels) and intervening lymph nodes whose function, like the venous system, is to return fluid from the tissues to be recirculated.

Interstitial fluid composition