Question

List the percent absorptive of secretion of sodium, potassium, water, bicarbonate, glucose for different regions of the nephron.

Answer 1

Substances	Proximal convoluted Tubule	Loop of Henle	Distal Convoluted Tubule	Collecting ducts
Sodium	65% of Reabsoprtion occurs through Active transport along with Glucose which is almost 100% reansorbed via Secondary active transport .	25% Reabsoprtion through Thick ascending Loop of Henle Active transport .	5% reabsorbed Active transport	5% Reabsoprtion occur in Collecting Duct through action of Aldosterone
Potassium	65% of Reabsoprtion occur here through Dissusion	20% of Reabsoprtion occurs through Thick Ascending Loop of Henle mainly through Diffusion	Secretion of Potassium occurs in DCT through Active transport	Aldosterone act on collecting duct and Cause Potassium Secretion in Collecting Duct Active transport through H+K+ ATP ase .
Water	65% of Reabsoprtion of water occur through Osmosis .It means water follows and it moves from low solute concentration to high solutes concentration	15% of Reabsoprtion through Osmosis through Descending Limb of Loop of Henle .	10% Reabsoprtion occur if ADH Antidiuretic hormone is present which acts on DCT and cause water Reabsoprtion and some amount of water occurs through Osmosis	10% of Reabsoprtion occurs which is Facultative free water rebasortion which occurs through Aquaporins inserted in Collecting Ducts which result in water Reabsoprtion .
Bicarbonate	90% of Bicarbonate is reabsorbed through Symport transport in which both Sodium and Bicarbonate is reabsorbed actively .	Ascending Limb of Loop of Henle -->Symport transport cause both Sodium and Bicarbonate to get reabsorbed and Antiport transport cause Sodium to get reabsored and Chloride is secreted .	No role	Reabsorbed through Antiport transport in which sodium is Reabsorbed and Chloride is secreted .
Glucose	100% Reabsoprtion of Glucose- occurs in PCT along with Sodium which is absorbed around 65% through secondary Active transport .	No role	No role	No role