The kidneys are critical for filtering blood and excreting waste products, including toxins, through urine. They achieve this through processes such as glomerular filtration, tubular reabsorption, and tubular secretion. Tubular secretion is particularly important as it involves the active transport of toxins from the blood into the renal tubule. This mechanism is crucial for the efficient removal of drugs and metabolites that might otherwise accumulate to toxic levels.
