USMLE Forum - Largest USMLE Community

hard physiology question (muti correct answer ques

yn28 - 11/24/06 23:36 #570548

Reabsorption of filtrated HCO3-
A. contribute to excretion titratable acid
B. is reduced during respiratory acidsis.
C. is acomplished by net serection of Na
D. is enhanced by carbonic anhydrase.

Can you please post the answer?

I will go for D.

Filtered HC03 reabsorbed in PCT...by reacting with H+..catalized by carbonic anhydrase inhibitor....gives rise CO2 & H20...

This Co2 enters into PCT.....Now this C02 reacted with H20 catalised by carbonic anhydrase inhibitor...Gives rise to H+ & HC03.....

This H+ secreted into renal tubuler lumen & simultaneously HC03 gets reabsorbed.

So Only carbonic anhydrase action can enhance HC03 reabsorption.
Ans................ddddddddddddd.

Filtered HC03 can reabsorbeed with Na... but in the answer of the qs...the choice C said Secretion of Sodium....So i didn't pick it.

What is the answer yn28????????????????????????????

Thx

bep111 , vat is the ans