Is lymph intracellular fluid?

Answer 1

Lymph is the material that moves through the lymphatic system. It is largely extracellular fluid (not intracellular), but also contains lymphocytes (white blood cells). Most of the fluid is squeezed from the blood stream into tissues and then moves into the lymphatic system. So, the composition of the fluid is somewhat like blood plasma.

Answer 2

The lymphatic system is a complex network of lymphoid organs, lymph nodes, lymph ducts, and lymph vessels that produce and transport lymph fluid from tissues to the circulatory system. The lymphatic system is a major component of the immune system.

The lymphatic system is comprised of three interrelated functions: (1) Removal of excess fluids from body tissues, (2) Absorption of fatty acids and subsequent transport of fat, chyle, to the circulatory system and (3) production of immune cells (such as lymphocytes, monocytes, and antibody producing cells called plasma cells).

Lymph originates as blood plasma that leaks from the capillaries of the circulatory system, becoming interstitial fluid, filling the space between individual cells of tissue. Plasma is forced out of the capillaries by hydrostatic pressure, and as it mixes with the interstitial fluid, the volume of fluid accumulates slowly. Most of the fluid is returned to the capillaries by osmosis. The proportion of interstitial fluid that is returned to the circulatory system by osmosis is about 90% of the former plasma, with about 10% accumulating as overfill. The excess interstitial fluid is collected by the lymphatic system by diffusion into lymph capillaries, and is processed by lymph nodes prior to being returned to the circulatory system. Once within the lymphatic system the fluid is called lymph, and has almost the same composition as the original interstitial fluid.