What organ excretes nitrogenous metabolic waste?

The organ that excretes nitrogenous metabolic waste is the kidneys. They filter blood to remove waste products, including urea, uric acid, and creatinine, which are byproducts of protein metabolism. These waste products are then excreted from the body in urine. The kidneys play a crucial role in maintaining the body's fluid and electrolyte balance while eliminating harmful substances.