Structure of the NEPHRON- A-level Biology. Ultrafiltration and selective reabsorption in the kidney

The lesson explains how the nephron’s structure (renal capsule, PCT, loop of Henle, DCT and collecting duct) enables ultrafiltration through a three-layered glomerular barrier and selective reabsorption via sodium-driven transport and medullary gradients to concentrate urine while retaining proteins and cells.