Female urinary system, artwork. The kidneys (top left and right) filter water-soluble waste products from the blood and pass them through the ureters (tubes, upper centre) into the bladder (oval, lower centre), where they are are stored as urine. When the bladder is full the urine is passed out of the body through the urethra (vertical tube, lower centre). The urethra opens into the vulval vestibule, the part of the vulva (bottom centre) between the labia minora (vertical pinkish folds) where the vaginal opening also opens.