Your kidneys are two bean-shaped organs, each about the size of your fist. They are located in the middle of your
back, just below your rib cage, on either side of your spine. Your kidneys weigh about 0.5 percent of your total body weight.
Although the kidneys are small organs by weight, they receive a huge amount, 20 percent, of the blood pumped by the heart.
The large blood supply to your kidneys enables them to do the following tasks:
*Regulate the composition
of your blood
*Keep the concentrations of various ions and other important substances constant
*Keep the volume
of water in your body constant
*Remove wastes from your body (urea, ammonia, drugs, toxic substances)
*Keep the
acid/base concentration of your blood constant
*Help regulate your blood pressure
*Stimulate the making of red
blood cells
*Maintain your body's calcium levels
Your kidneys receive the blood from the renal
artery, process it, return the processed blood to the body through the renal vein and remove the wastes and other
unwanted substances in the urine. Urine flows from the kidneys through the ureters to the bladder. In the bladder, the urine
is stored until it is excreted from the body through the urethra.
