Final answer:
The organ responsible for filtering metabolic wastes, ions, and drugs from the blood and expelling them through urination is the kidney. These bean-shaped organs maintain fluid, electrolyte balance, and the filtration of blood to produce urine.
Step-by-step explanation:
The organ that filters metabolic wastes, ions, and drugs from the blood and expels them from the body via urination is the kidney. The kidneys are a pair of essential organs situated near the posterior side of the abdomen. They have several critical functions, one of the most important being to filter the blood that passes through them. This filtration process removes waste products that originate from the normal breakdown of tissues and from food. The kidneys also play a crucial role in maintaining the body’s water balance and the pH level of bodily fluids. Wastes, along with excess water, form urine, which is collected in the urinary bladder and eventually excreted from the body.
In addition to the kidneys, other organs of the excretory system include the skin, which expels sweat, the liver, which excretes waste products such as bilirubin, the lungs that eliminate carbon dioxide and water vapor, and the large intestine, which removes solid waste. Nevertheless, the kidneys are the main osmoregulatory organs, using a vast amount of the body's oxygen to filter blood and forming filtrate, which becomes urine.