What is the function of the urinary system in vertebrates?
Filtering waste from the blood.
When you digest food and liquids, your intestines absorb those nutrients and then send them to your cells in the form of usable energy. After your cells have used that energy, the remains (waste) are put back into the blood. Your kidneys then filter this waste out of your blood, and those wastes, along excess liquids, are ejected from your body through the urinary system.