The body fluids found outside the cells, such as plasma (the liquid portion of blood and lymph), and interstitial fluid, are generically termed extracellular fluid. Three-fourths of all extracellular fluid is stored as interstitial (between cells)...

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Extracellular fluid (ECF) usually denotes all body fluid outside of cells. The remainder is called intracellular fluid. In some animals, including mammals, the extracellular fluid can be divided into two major subcompartments, interstitial fluid and...

In order for our body cells to function properly, they must be surrounded in extracellular fluid that is relatively constant with regard to osmolality. The kidneys, in concert with neural and endocrine input, regulate the volume and osmolality of the extracellular fluid by...

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