Ultrafiltration in the kidney takes place in the

Ultrafiltration in the kidney takes place in Bowman's capsule. Bowman's capsule is a cup-shaped structure at the beginning of each nephron in the kidney. Blood flows into the nephron through the afferent arteriole and into the glomerulus, a cluster of tiny blood vessels. The high pressure in the glomerulus forces small molecules, such as water, ions, and waste products, out of the blood and into Bowman's capsule. This process is called ultrafiltration, and it is the first step in urine formation. The filtered fluid then flows through the rest of the nephron, where important substances are reabsorbed back into the bloodstream and the final urine is produced.