Nephron (magnified inset)
Nephron
UrinaryOrgansWhole body
- What it is
- Schematic enlargement of one juxtamedullary nephron, the kidney's filtering unit: the renal corpuscle and convoluted tubules sit in the cortex (above the line), the loop of Henle and collecting duct run down into the medulla (below it).
- Function
- Each nephron filters blood and then reabsorbs or secretes water and solutes along its tubule to produce urine.
- Size
- About 1 million per kidney; a nephron tubule is 3–5 cm long but only ~50 µm wide (not drawn to one scale).
- Clinical note
- About 85% of nephrons are cortical with short loops; the 15% juxtamedullary nephrons with long loops make concentrated urine possible.