What are the kidneys?
Your kidneys are 2 bean-shaped organs that produce urine. They’re about the size of your fist. They're in the back of your abdomen, on either side of your spine.
Kidneys balance your body’s water and mineral levels and filter waste out of your blood.
Damage to one kidney doesn't cause major problems as long as your other kidney works—both of your kidneys need to stop working for you to have serious problems.
The main job of your kidneys is to maintain the balance of water About Body Water About half your body weight is water. So if you are a 160-pound woman, you have about 80 pounds (10 gallons) of water in your body. You need the right amount of water in your body for good health... read more and electrolytes Overview of Electrolytes Electrolytes are minerals that circulate in your blood. These minerals are also in your stomach juices, in your stool (poop), in your urine, and inside your body's tissues. Salt (sodium) is... read more in the body
They do this job by adjusting how much water and electrolytes go into the urine
Kidneys also filter waste products, help control your blood pressure, and secrete (let out) certain hormones
What is the urinary tract?
The urinary tract is the passage that carries urine out of your body. Your urinary tract consists of:
Kidneys
Ureters
Bladder
Urethra
The Urinary Tract
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The kidneys make urine, which drains through the ureters and into the bladder. From the bladder, urine passes into the urethra. Urine exits the body through the penis in males and the vulva in females.
Ureters
Your ureters are muscular tubes that carry urine between your kidneys and bladder. They squeeze to push the urine along.
Bladder
Your bladder is a muscular sac that holds your urine. It expands to store urine made by your kidneys.
When your bladder is full, nerve signals tell you to empty it. The urinary sphincter opens, and urine passes into your urethra.
Urethra
Your urethra is a tube that carries urine out of your body.
Men have a urethra that ends at the tip of the penis. Women have a much shorter urethra that ends at the vulva. A shorter urethra means it's easier for bacteria from outside the body to get into the bladder and cause urinary tract infections Urinary Tract Infections (UTI) .