Urine is primarily composed of waste products filtered from the blood by the kidneys. These wastes include:
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Urea: This is the main waste product of protein breakdown. As stated in the provided text, "Urea is made when foods containing protein (such as meat, poultry, and certain vegetables) are broken down in the body." The kidneys filter urea from the blood and excrete it in the urine.
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Salts: Various salts, including sodium and potassium, are also present in urine. The kidneys regulate the balance of these electrolytes in the body, excreting excess amounts through urine.
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Toxins: The kidneys filter out toxins and other harmful substances from the blood, removing them from the body via urine. This helps maintain overall bodily health.
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Water: Urine consists largely of water, acting as a solvent to carry the dissolved waste products. The kidneys manage the body's water balance, adjusting the amount of water in urine depending on hydration levels.
The urinary system, encompassing the kidneys, ureters, bladder, and urethra, works in concert to filter blood, produce urine as a waste by-product, and store and eliminate it from the body. As noted in the provided text from Johns Hopkins Medicine, "The urinary system's function is to filter blood and create urine as a waste by-product." The composition of urine can vary slightly depending on factors such as diet, hydration, and overall health. Furthermore, the presence of certain substances, like excess protein, in urine can indicate underlying health issues.
