Location
- Primarily proximal convoluted tubules
Process
- CO2 combines with water to form carbonic acid, catalysed by carbonic anhydrase
- H2CO3 dissociates to form to H+ and bicarbonate
- H+ ions are secreted into the tubular lumen in exchange for Na+
- Na+ ions and HCO3- are reabsorbed into the blood
Result
- Net excretion of hydrogen ions
- Net generation of bicarbonate