Answer: renal vein
Urine passes thru large channels called (ducts) which drain into the renal pelvis or (inner part of the kidney). Next, the urine passes thru a ureter then afterward goes from each kidney to the bladder. Urine is then stored in the bladder while the “cleaned' (filtered) blood” from each kidney go into a large blood vessel called the renal vein. This vein gets the blood back to the heart.
