The body is made of different systems that help maintain daily functions. One of these many systems is the Excretory System. The primary organs in this system are the lungs, kidneys, and skin. Of most of these organs, the Kidneys are overlooked. They are very important to the body and accomplish many tasks every day. Kidneys usually come in pairs, although sometimes you can live with just one. They look like a kidney bean and each one is about 5 inches long and about 3 inches wide. One is about the size or a fist or a computer mouse. They are located in the lower back near the twelfth rib. It sits within perirenal fat and renal fascia that protect against injury.
There are many jobs that the kidney does. One of them is getting rid of wastes and making urine. When your blood delivers nutrients to your body, chemical reactions occur in the cells of the body to break down nutrients. Some waste is the result of the chemical reactions and some is stuff that the body does not need. Blood is carried into the kidneys by the renal artery. About 400 gallons of recycled blood are pumped through them every day. The waste is then collected out of the blood by tiny filters, or nephrons, inside the kidneys. There are about over one million nephrons inside each kidney. The waste collected combines with water to make urine. As this happens, the urine slides down a long tube, the ureter, and collects in the bladder, a storage sac that holds the urine. When the bladder is about halfway full, the body tells the person they need to go to the bathroom. When you do this, the urine goes from the bladder to another tube, the urethra, and out of the body. .
The kidneys also balance the volume of fluids and minerals in the body, or Homeostasis. Water leaves the body in several ways. It comes out of the mouth when breathing, out of the skin when you sweat, and out of the urethra in urine. .
The brain also communicates with the kidneys by sending out a hormone that tells the kidneys to hold onto more fluids when feeling thirsty.