intravascular and interstitial body fluid compartments

The image above shows the composition of the cell membrane that separates the extracellular fluid of a cell from the intracellular fluid (cytoplasm). sodium moves out of the cell and potassium is pumped in) and maintain the gradients inside and outside the cell. The pumps are powered by adenosine triphosphate (ATP) to provide the energy to move the ions against their concentration gradients (i.e. While water moves passively via osmosis, sodium and potassium ions move in and out of cells using active transport ion pumps. The plasma has high concentrations of sodium, chloride, and bicarbonate, but lower levels of protein as compared to the ICF. The ICF has higher amounts of potassium, phosphate, magnesium, and protein compared to the ECF. Concentrations of intracellular and extracellular cations are as follows: Intracellular potassium concentration averages 140 mEq/L (140 mmol/L). The major extracellular cation is sodium. The major intracellular cation is potassium. The Movement of Solutes Between Compartments Fluid compartments in an average 70-kg man Total body water 70 kg × 0.60 42 L (280 mOsm/kg 280 mmol/kg). In mammals, milk is also considered an extracellular fluid. The balance consists of cerebrospinal fluid, lymph, the synovial fluid in the joints, pleural fluid in the pleural cavities (lungs), pericardial fluid around the heart, peritoneal fluid in the peritoneal cavity (abdomen), and the aqueous humor of the eye. The two main components of ECF are plasma and interstitial fluid (IF). ECFs are any body fluids that are not inside cells.

Intravascular and interstitial body fluid compartments