What are three functions of the excretory system

Helps eliminate waste products such as urea, uric acid ammonia, and other products via urine.

It helps maintain the osmotic level of blood and plasma.

It helps maintain the electrolyte balance in the body.

And it also helps in the metabolism of those drugs that do not get metabolized in the liver.

Explanation:

"The excretory system is a passive biological system that removes excess, unnecessary materials from the body fluids of an organism, so as to help maintain internal chemical homeostasis and prevent damage to the body. The dual function of excretory systems is the elimination of the waste products of metabolism and to drain the body of used up and broken down components in a liquid and gaseous state"