The role of the kidneys
Reviewed by Dr Jonah Mink, April 21'
Located on the right and left sides of your spine under your lower rib cage, the kidneys are the primary bean-shaped organs of the urinary system.
After you’ve eaten a meal, your body absorbs nutrients from food and transforms them into energy. This process leaves behind waste products in the bowel and the blood.
The kidneys help filter waste and extra water from the blood by forming urine. Your urine then goes on a bit of a journey.
1. From the kidneys, urine passes through two thin tubes to the bladder. These tubes are called ureters and they’re approximately 20cm to 25cm long. Your ureters force urine downwards, away from the kidneys, by tightening and relaxing the muscles in their walls.
2. Every 10 to 15 seconds, a small amount of urine is emptied into your bladder from the ureters. Your bladder is a hollow, balloon-shaped organ located in your pelvis where urine is stored. In fact, it can comfortably hold up to half a litre of urine for two to five hours.
3. When your bladder is full, your brain sends a signal that you’re ready to empty it. Your urine is then squeezed through a thin tube called the urethra to get rid of the waste. The length of the urethra in females is around 1.5 to 2 inches long and located between the clitoris and the vagina.