©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
PHS3300 Acid-Base Balance Exam Questions
With Correct Answers
Acid - answer✔compound that forms H+ ions in solution
base - answer✔compound that produces OH- ions in solution
as [H+] ___, pH ____ - answer✔increases, decreases
normal arterial pH - answer✔7.4
-normal range: 7.35 to 7.45
acidosis - answer✔pH < 7.35
alkalosis - answer✔pH > 7.45
pH depends on...? - answer✔[HCO3-] from kidney/PCO2 from lungs
-kidneys: metabolic, plasma HCO3-
-lungs: respiratory, pCO2
ratio of HCO3 to H2CO3 - answer✔-20:1
-if H2CO3 increases, HCO3 must to maintain normal values
normal HCO3- - answer✔24mM
normal H2CO3 - answer✔1.2mM
acid base equation - answer✔H2O + CO2
H2CO3
HCO3- + H+
how do kidneys produce HCO3-? - answer✔1. convert buffered acids into more acid salts
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, ©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
2. kidneys produce new HCO3 (glutamine = NH4 + HCO3)
where is HCO3 lost? - answer✔-gut
-neutralizing of HCl
when is HCO3- production impacted? - answer✔-when only 30% nephrons remain
-GFR drop by 70%
steps of HCO3 recycling in kidneys - answer✔1. Na from glomerular filtrate goes into tubular
cell
2. H+ from tubular cell goes into glomerular filtrate
3. H+ and HCO3- in glomerular filtrate make H2CO3
4. H2CO3 dissociates into CO2 and H2O
5. H2O and CO2 go back into tubular cell, join to make H2CO3
6. H2CO3 dissociates into HCO3- and H+
7. HCO3- goes into plasma
stimulus to kidney altering HCO3- production - answer✔1. decrease in pH (acidosis) = increase
HCO3-
2. increase in pH (alkalosis) = decrease HCO3-
is renal compensation to pH change ST or LT? - answer✔LT: days to weeks
stimulus to lungs altering pCO2 production - answer✔1. decrease in pH (acidosis) = increase
ventilation, decrease CO2
2. increase in pH (alkalosis) = decrease ventilation, increase CO2
is lung compensation to pH change ST or LT? - answer✔ST: immediate
types of changes in blood pH - answer✔metabolic OR respiratory
normal plasma HCO3- - answer✔22 to 28 mM
metabolic acidosis - answer✔< 22 mM
-indicates deficit in base
-decreases pH
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11/16/2024 10:16 AM
PHS3300 Acid-Base Balance Exam Questions
With Correct Answers
Acid - answer✔compound that forms H+ ions in solution
base - answer✔compound that produces OH- ions in solution
as [H+] ___, pH ____ - answer✔increases, decreases
normal arterial pH - answer✔7.4
-normal range: 7.35 to 7.45
acidosis - answer✔pH < 7.35
alkalosis - answer✔pH > 7.45
pH depends on...? - answer✔[HCO3-] from kidney/PCO2 from lungs
-kidneys: metabolic, plasma HCO3-
-lungs: respiratory, pCO2
ratio of HCO3 to H2CO3 - answer✔-20:1
-if H2CO3 increases, HCO3 must to maintain normal values
normal HCO3- - answer✔24mM
normal H2CO3 - answer✔1.2mM
acid base equation - answer✔H2O + CO2
H2CO3
HCO3- + H+
how do kidneys produce HCO3-? - answer✔1. convert buffered acids into more acid salts
1|Page
, ©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
2. kidneys produce new HCO3 (glutamine = NH4 + HCO3)
where is HCO3 lost? - answer✔-gut
-neutralizing of HCl
when is HCO3- production impacted? - answer✔-when only 30% nephrons remain
-GFR drop by 70%
steps of HCO3 recycling in kidneys - answer✔1. Na from glomerular filtrate goes into tubular
cell
2. H+ from tubular cell goes into glomerular filtrate
3. H+ and HCO3- in glomerular filtrate make H2CO3
4. H2CO3 dissociates into CO2 and H2O
5. H2O and CO2 go back into tubular cell, join to make H2CO3
6. H2CO3 dissociates into HCO3- and H+
7. HCO3- goes into plasma
stimulus to kidney altering HCO3- production - answer✔1. decrease in pH (acidosis) = increase
HCO3-
2. increase in pH (alkalosis) = decrease HCO3-
is renal compensation to pH change ST or LT? - answer✔LT: days to weeks
stimulus to lungs altering pCO2 production - answer✔1. decrease in pH (acidosis) = increase
ventilation, decrease CO2
2. increase in pH (alkalosis) = decrease ventilation, increase CO2
is lung compensation to pH change ST or LT? - answer✔ST: immediate
types of changes in blood pH - answer✔metabolic OR respiratory
normal plasma HCO3- - answer✔22 to 28 mM
metabolic acidosis - answer✔< 22 mM
-indicates deficit in base
-decreases pH
2|Page
