Excretory system

The metabolism of our cells produces waste products that should be discarded. The organs performing this function are:
- the lungs, which excrete carbon dioxide;
- the kidneys, which eliminate water and a few chemical substances, especially salts;
- the intestine, which eliminates the substances that are not absorbed during digestion through the rectum;
- the skin, which eliminates water and minerals (as the kidneys).


