Answer:
Excretory System
Explanation:
Kidneys play a crucial role in the body's excretory system, which is the organ system that controls the excretion of harmful products from the body.
The main pathway here is:
kidneys --> ureters --> bladder --> urethra
But, it's true that within the kidney, the levels of organization are:
kidney cells or nephrons (kidney formula units) --> kidney tissues --> kidney
