Lymph

Lymph originates from interstitial fluid.

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Interstitial fluid is the body fluid between blood vessels and cells,[8] containing nutrients from capillaries by diffusion and holding waste products discharged by cells due to metabolism.[9][10] 11 liters of the ECF are interstitial fluid and the remaining three liters are plasma.[7] Plasma and interstitial fluid are very similar because water, ions, and small solutes are continuously exchanged between them across the walls of capillaries, through pores and capillary clefts. [citation needed]

Interstitial fluid consists of a water solvent containing sugars, salts, fatty acids, amino acids, coenzymes, hormones, neurotransmitters, white blood cells and cell waste-products. This solution accounts for 26% of the water in the human body. The composition of interstitial fluid depends upon the exchanges between the cells in the biological tissue and the blood.[11] This means that tissue fluid has a different composition in different tissues and in different areas of the body. [citation needed]

The plasma that filters through the blood capillaries into the interstitial fluid does not contain red blood cells or platelets as they are too large to pass through but can contain some white blood cells to help the immune system. [citation needed]

Once the extracellular fluid collects into small vessels (lymph capillaries) it is considered to be lymph, and the vessels that carry it back to the blood are called the lymphatic vessels. The lymphatic system returns protein and excess interstitial fluid to the circulation. [citation needed]

The ionic composition of the interstitial fluid and blood plasma vary due to the Gibbs–Donnan effect. This causes a slight difference in the concentration of cations and anions between the two fluid compartments. [citation needed]

 

 

 

Lymph contains lymphocytes and other white blood cells. It also contains water, proteins, fats, immune cells (lymphocytes), debris of cells, bacteria and waste products.

The constituents of the blood first exit the microvascular exchange blood vessels to become interstitial fluid, which comes into contact with the parenchymal cells of the body.

Lymph is the fluid that is formed when interstitial fluid enters the initial lymphatic vessels of the lymphatic system. The lymph is then moved along the lymphatic vessel network by either intrinsic contractions of the lymphatic passages or by extrinsic compression of the lymphatic vessels via external tissue forces (e.g., the contractions of skeletal muscles), or by lymph hearts in some animals. The organization of lymph nodes and drainage follows the organization of the body into external and internal regions; therefore, the lymphatic drainage of the head, limbs, and body cavity walls follows an external route, and the lymphatic drainage of the thorax, abdomen, and pelvic cavities follows an internal route.[5]Eventually, the lymph vessels empty into the lymphatic ducts, which drain into one of the two subclavian veins, near their junction with the internal jugular veins.

Reference

1. https://www.slideshare.net/prennievidiera/lymph-44422935

Lymphatic System

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