Wikijunior:Human Body/ExcretorySystem

The excretory system is how our bodies get rid of things they don't need. This is called waste. The urinary system is a part of this, but there are also other organs that help our bodies get rid of waste.

What does the excretory system look like? (Appearance)


The largest organs in the excretory system are the kidneys. There are 2 of them. They are shaped like large reddish brown beans. They are about the size of a fist and are located on each side of your back.

Running from the kidneys to the bladder are two long skinny tubes called ureters.

The bladder is a hollow organ that holds urine. It can stretch to hold more liquid. There is another tube called the urethra that carries urine out of the body.

The excretory system also includes skin and lungs to expel waste.

What are the parts of the excretory system? (Parts)
There are several parts of the excretory system. To get rid of liquid waste in our bodies, we have two kidneys, two ureters, a bladder, and a urethra.

Kidneys filter our blood to get rid of things in our blood that are not needed. If we didn’t have kidneys, we would eventually be poisoned by this waste. The kidneys are full of millions of microscopic things called nephrons. They filter the blood and produce urine. Urine is the liquid that leaves your body when you go to the bathroom.

The urine travels down two tubes called ureters to get to the bladder. The bladder is where urine is stored until you go to the bathroom. The last tube the urine goes through to leave the body is called the urethra.

Solid wastes leave the body through the rectum, as described in the section on the digestive system. The lungs are also a part of the excretory system. They get rid of the carbon dioxide that our bodies don’t need. This happens when we breathe out, as is described in the section on the respiratory system.

One other part of the excretory system is our sweat glands. The purpose of sweat glands is to keep our bodies cool and also to get rid of wastes, including salts that our body doesn’t need. Sweat glands are in your skin, and there are over 2 million of them in each person!

What is the function of the excretory system? (Function)
There are some things in our body that can’t be used and may even be dangerous to your body. They need to be gotten rid of. The job of the excretory system is to get rid of that waste.

How does the excretory system interact with other parts of the body? (Interactions With Other Body Parts)
All of our blood runs through our kidneys every day. There is an artery and a vein that runs in and out of each kidney to take the blood there and back.

Solid waste is filtered out by the digestive system.

Without the excretory system, the other parts of the body would eventually be poisoned by waste.

How can you keep your excretory system healthy? (Health)
Make sure to eat healthy foods and drink plenty of water. If you have any pain when you go to the bathroom, make sure to tell someone, so they can see if something is wrong.

If you have diarrhea or sweat too much, your body may lose too much fluids and salts. Make sure to drink lots of water to replenish your body. You may also need to drink a sports drink.