How Do Kidney Cells Contribute to Filtration and Reabsorption?
The glomerulus, with its capillaries lined by endothelial cells and supported by podocytes, is the initial site of filtration. Blood pressure forces water and small molecules through the filtration membrane into the Bowman's capsule, forming the filtrate.
Proximal tubule cells then reabsorb nearly 65% of the filtrate, including glucose, amino acids, and ions, through active and passive transport mechanisms. Distal tubule cells and collecting duct cells fine-tune the composition of urine by reabsorbing additional ions and water, regulated by hormones like aldosterone and antidiuretic hormone (ADH).
