Question

1. During bicarbonate (HCO3) reabsorption, what is the intracellular chemical reaction that produces the HCO, that is ultimately reabsorbed. Is this reaction the same in both the proximal and distal tubules? If not, what is different? 2. (A) In the proximal tubule, what is the major H-secreting mechanism? (B) In the collecting duct (distal nephron), how are protons secreted? 3. (A) A patient is undergoing intestinal surgery. A tube is inserted into the duct leading to the pancreas and fluid is then drained into a disposal bottle. If this pancreatic fluid contains high [HCO3 ], will the blood be acidified or alkalinized? (B) If [HCO) in the drainage fluid is 75 mM in a total of 2 litres drained fluid, what is the total [H] load that enters the extracellular fluid? 4. During a 12-hr period, a person excretes 45 meq of net acid. How much net HCO, is added to the body fluids during that period? 5. Assume that endogenous acid production is 40 meq during a 12-hr period. A urine sample collected during this time contains 30 mmol NH4 and 15 meq titratable acid. If the body is in steady state for HCO;, how much HCO,' must be in this urine sample?

Answer 1

an it with Nat and Anstlerson O Biocarbonate. PCT :-80 to 90% Sympost ou absophion with not koop of Henle - Reabsorbed Sympas! ei with ei in ascending limb. Colleching duct - Reabsorbed antipout with all ea proximal convoluted tobule secrector of Htions by b) actively secret hit sons in Collecting dedi diffusion downed Schernally. A) Since, Hico, is alkaline fleted has been the blood would be acidified . extracellular fluid - Total [Hoz] drained. 3 Total (H+7 added to Numbea of moles - Volume x molarity = 10 3 x 2 x 75 = 0.15 moles. ☺ - usmea acid Excereted in 12 hrs. hence in 24hr = 45x2 - gomeg Bagicity of acid Acidity of base al Quantity of Hoz a 90 meq / 12hr = 90x1 - 90mmol.

I prodoction in 12 hours = 40m eq for autos - someq - Bome [C10x2] Orine Sample → Nhurt = 30mmol. Acid = 15meq . HCoz" present in Quirine Sample Cautrs). = 80-30-15 -50-15 = 35 mmol. HCor present in urine Sample for auhisa 5mmol.