The Nephron

Blood enters the nephron through the afferent arteriole, which leads to the glomerulus, a cluster of capillaries where filtration occurs. Here, water, ions, and small molecules are filtered out of the blood into the Bowman’s capsule, while larger components like blood cells and proteins remain in the bloodstream. The filtered fluid, called filtrate, then flows through the proximal convoluted tubule, where essential substances like glucose, amino acids, and water are reabsorbed. It continues into the loop of Henle, where water and salts are further reabsorbed to concentrate the filtrate. Next, it moves through the distal convoluted tubule, which fine-tunes salt and pH balance. Finally, the fluid enters the collecting duct, where the final composition of urine is determined before it is transported to the renal pelvis for excretion.