How do kidneys filter waste from your blood?

Blood enters each kidney through the renal artery and flows into about a million tiny filtering units called nephrons. Each nephron contains a glomerulus, a small cluster of capillaries where blood pressure forces water, salts, glucose, urea, and other small molecules out of the blood and into a cup-shaped structure called Bowman's capsule. This filtered fluid then travels through a series of tubules where the body reclaims useful substances like glucose, water, and essential ions back into the bloodstream. What remains after this reabsorption process is concentrated waste, which becomes urine. The urine drains into the renal pelvis, travels down the ureter, and collects in the bladder until it is excreted.