The answer is why ........
<span>the answer is the gall bladder.</span>
The answer should be the ureter. It's a tube to carry urine, which contains urea and other waste like salt or water down to the urinary bladder.
Kidney is used to filter components from the blood to form urine, it collects useful substances and remove useless substances, where the useless substance forms urine, while the urinary bladder is used to hold urine until Excretion.
Therefore the answer should be ureter and urinary bladder.
