Kidneys and their Functions

The major function of kidneys is to filter the redundant nutrients and metabolites out of the blood, including those that come from the natural breakdown of tissues as well as those that we ingest with food intake. In this way, the kidneys maintain the homeostatic balance with respect to water and electrolytes as well as nutrients and metabolites. In addition, the actions of the kidneys also regulate blood pressure and erythropoiesis. 

The blood first reaches the glomerulus, the filter unit of the nephron. The glomerular filtrate, i.e. blood deprived of macromolecules and blood cells, passes through the tubular lumen. The blood which is not filtered, flows through the efferent arteriole into the network of capillaries around the tubules suppl5dng the proximal and distal tubules with blood. 

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