Urine is the liquid waste product of the body that is excreted by the urinary system.
Urine tests detect drugs used up to 36 hours before a given urine collection.
The urinary system excretes a substance used in drug testing.
Which bodily system excretes a substance commonly used in drug testing?
  * Evaporation
  * urinary system
  * animals
  * aqueous solution
  * cardiovascular system
  * opiate system
  * Integumentary system
  * sweating