What are the major homeostatic roles of the kidneys in normal healthy adults?

The major homeostatic roles of kidneys in a healthy adults include; Regulation of the extracellular fluid volume, they ensure an adequate quantity of plasma to keep blood flowing to the vital organs. Regulating osmolarity; the kidneys help maintain appropriate concentration of the extracellular fluid with respect to the solutes in the fluid. The kidney regulates ion concentration ; including the sodium, calcium and potassium ions;. They also regulate the body pH; by preventing the blood plasma from being too acidic or basic. Another role is excretion of wastes and toxins, and lastly the production of hormones, such as erythropoietin which stimulates the synthesis of red blood cell.

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