The excretory system

Our body produces waste substances which go into the blood, and can be dangerous.
Excretion is the elimination of these waste substances.

-The kidneys are the organs of the excretory system. These two organs filter the blood and produce urine. This is made up of water (95%) and waste substances (5%). The urine leaves the kidneys and passes through the ureters, two tubes which go to the bladder. The urine accumulates there until it is expelled through the urethra.

-The sweat glands in the skin also help in excretion. They make sweat.