The lymphatic system of the human body is a complex mechanism that is based on the interaction of many different cells. One of the main elements of the lymphatic system is interstitial fluid, which is also called a tissue fluid, a solution surrounding the cells of all multicellular animals, including humans. The interstitial fluid is essential for the provision of vital nutrients to the cells of the body (Hall & Hall, 2020). The interstitial fluid is caused to accumulate in tissues due to the hydrostatic pressure that the heart generates. Essentially, the pressure leads to capillaries losing water, which then passes from outside the lymphatic vessels, where it has high concentration, to inside the lymphatic vessels, where the concentration becomes low, a process called osmosis.
The primary task of lymphatic vessels is carrying fluid away from the tissues in the body. The lymph capillaries are considered to be the smallest lymphatic vessels, and they form in the tissue spaces as blind-ended sacs. The lymph is formed during the moment when the interstitial fluid enters the lymph capillaries, despite the fact that they are of microscopic size (Hall & Hall, 2020). Lymph capillaries can be discovered almost in all parts of the human body, with the exception of the central nervous system, epidermis, and several other elements. The wall of the lymph capillary has a one-way valve that allows it to accumulate fluid while preventing it from leaving. Eventually, lymph capillaries fuse together and thus form lymphatic vessels, which, in their turn, further join to create lymphatic trunks. In the end, the lymph enters the two lymphatic ducts, one of which drains lymph from the upper right quadrant of the body, while another drains the remaining part.
Reference
Hall, J., & Hall, M. (2020). Guyton and Hall textbook of medical physiology. Elsevier Health Sciences.