Watch this video if you want to learn about the structure of the lymphatic capillaries and vessels and how they pump the lymphatic fluid into the circulation against the gravity by establishing unidirectional flow. Timeline: 0:00 - Introduction 0:35 - Structure and function of lymphatic vessels 3:40 - Edema 4:14 - Close look at lymphatic vessel 5:04 - Valves and unidirectional flow 5:51 - Smooth muscle wall 6:39 - Skeletal muscle pump