Body fluids are distributed in two distinct compartments. Briefly explain each one.

Body fluids in the human body are distributed in two main compartments: the intracellular fluid compartment and the extracellular fluid compartment.

1. Intracellular Fluid Compartment: This is the largest compartment and contains about two-thirds of the body water. Intracellular fluid (ICF) is the fluid found within the cells of the body. The metabolic processes of the cell occur in this fluid. The composition of ICF is distinct from the extracellular fluid and it contains higher concentrations of potassium, phosphate, and magnesium ions.

2. Extracellular Fluid Compartment: This compartment contains the remaining one-third of body water. Extracellular fluid (ECF) is the body fluid outside of the cells, and it includes interstitial fluid (the fluid in the spaces between the cells), blood plasma, and the fluid found in other reservoirs such as the lymph, cerebrospinal fluid, and fluid in the eyes. The ECF acts as a transport medium for delivering nutrients to the cells and carrying waste products away from the cells. It contains higher concentrations of sodium, chloride, and bicarbonate ions.

These two compartments are not isolated from each other and there is a constant exchange of substances between them to maintain homeostasis in the body.