Narrowed Renal Artery Anatomy
The kidneys are located in the back of the abdomen, below the ribcage and on either side of the spine. Each kidney weighs about 1/4 pound (0.6 kg) and is about the size of a fist. The kidneys filter waste from the bloodstream and produce urine. The kidneys also regulate the salt and water balance for the body. Urine leaves the kidneys and travels to the bladder via the ureters.
In an adult, the bladder can hold 10 to 20 ounces of urine -- about as much liquid as in one can of soda. When the bladder is about half full, you may begin to feel the need to empty it by urinating. Urine is carried out of the body through the urethra, a tube at the bottom of the bladder.
The urinary tract is broken down into two areas:
- Upper urinary tract: includes the kidneys and ureters.
- Lower urinary tract: includes the urethra and bladder.
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