Know a bit about your kidneys

You have two kidneys. They are each about the size of your clenched fist. They lie on either side of your spine behind the lower end of your rib cage. If you stand with the flat of your hands resting on your waist, thumbs forwards, your kidneys are roughly under the heel of your hands.

Blood flows into each kidney through its renal artery and it flows out of each kidney through its renal vein. The function of the kidney is to draw impurities out of the blood that flows through it so that blood returning to the circulation from the kidney via the renal vein is clean and pure. The kidney dissolves these impurities in water, which is what makes urine. Urine passes from each kidney to your bladder through two tubes called the ureters.