Lymph capillary - wikipedia Lymph capillary Lymphatic capillary Diagram showing the formation of lymph from interstitial fluid ( labeled here as `` Tissue fluid '' ). Note : how the tissue fluid is entering the blind ends of lymph capillaries ( indicated by deep green arrows ) Details System Lymphatic system Identifiers Latin vas lymphocapillare TA A12. 0.00. 044 TH H3. 09.02. 0.05004 FMA 5028 Anatomical terminology ( edit on Wikidata ) Lymph capillaries or lymphatic capillaries are tiny, thin - walled vessels located in the spaces between cells ( except in the central nervous system and non-vascular tissues ) which serve to drain and process extra-cellular fluid. Upon entering the lumen of a lymphatic capillary, the collected fluid and associated cells ( notably white blood cells ) is known as lymph. Each lymphatic capillary carries lymph into a lymphatic vessel, which in turn connects to a lymph node. Lymph is ultimately returned to the venous circulation. Lymphatic capillaries are slightly larger in diameter than blood capillaries, and have closed ends ( unlike the loop structure of blood capillaries ). Their unique structure permits interstitial fluid to flow into them but not out. The ends of the endothelial cells that make up the wall of a lymphatic capillary overlap. When pressure is greater in the interstitial fluid than in lymph, the cells separate slightly, like the opening of a one - way swinging door, and interstitial fluid enters the lymphatic capillary. When pressure is greater inside the lymphatic capillary, the cells adhere more closely, and lymph can not escape back into interstitial fluid. Attached to the lymphatic capillaries are anchoring filaments, which contain elastic fibers. They extend out from the lymphatic capillary, attaching lymphatic endothelial cells to surrounding tissues. When excess interstitial fluid accumulates and causes tissue swelling, the anchoring filaments are pulled, making the openings between cells even larger so that more fluid can flow into the lymphatic capillary. Lymph capillaries have a greater internal oncotic pressure than blood capillaries, due to the greater concentration of plasma proteins in the lymph. References Jump up ^ Tortora, Gerard J. : `` Principles of Human Anatomy - 10th edition '', page 512. John Wiley and Sons, Inc., 2005. lymph enters the lymph capillaries by osmosis Arteries and veins Vessels Arteries Nutrient artery Arteriole Metarteriole Elastic artery Capillaries Types Continuous Fenestrated Sinusoidal Precapillary sphincter Precapillary resistance Veins Vena comitans Superficial vein Deep vein Emissary veins Venous plexus Venule Lymph Lymphatic vessel Lymph Lymph capillary Circulatory system Systemic Left heart → Aorta → Arteries → Arterioles → Capillaries → Venules → Veins → Vena cava → ( Right heart ) Pulmonary Right heart → Pulmonary arteries → Lungs → Pulmonary vein → Left heart Microanatomy Microvessel Microcirculation Tunica intima Endothelium Internal elastic lamina Tunica media Tunica externa Vasa vasorum Vasa nervorum Vascular nerves Rete mirabile Circulatory anastomosis Lymphatic vessels Nodal Lymph capillary Lymphatic vessel Other Lymph trunk Lymph Lymphangion Retrieved from `` https://en.wikipedia.org/w/index.php?title=Lymph_capillary&oldid=827091671 '' Categories : Lymphatic organ anatomy Angiology Hidden categories : Pages with unresolved properties Talk About Wikipedia Eesti Español Português Edit links This page was last edited on 22 February 2018, at 18 : 46 ( UTC ). Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: when do anchoring filaments open spaces between endothelial cells in lymph capillaries
Answer: When excess interstitial fluid accumulates and causes tissue swelling