25 Acid-Base Homeostasis and Imbalance Flashcards
death range of pH
too acidic<6.9-7.8
maintenance of acid-base balance reflects homeostatic functions of ___
normal cellular metabolism
if pH is too acidic, proteins will ____
get denatured
normal pH
7.35-7.45
normal PaCO2
36-44 mmHg
normal HCO3-
22-26 mEq/L
useful indicators of acid-base status of ECF
arterial blood gas [ABG]
PaCO3 indicates ___
how effectively the respiratory sytm is excreting carbonic acid
lung/respiratory function
HCO3- indicates ___
effectiveness of renal regulation of metabolic acids
- excess or deficit of metabolic acids
- renal/metbolic function
3 major systems to regulate acid-base
1 buffer
2 respiratory sytm
3 renal sytm
compensatory mechanisms to regulate acid-base
respiratory + renal system
first line of defense against pH changes in all body fluids
Bicarbonate Buffer system
chemicals that help control pH of body fluids
1 Bicarbonate ions [HCO3-]
2 Carbonic acid [H2CO3]
Bicarbonate Ions
HCO3-
basic
-takes up H when fluid is too acidic
Carbonic Acid
H2CO3
weak acid
-release H ions when fluid is too alkaline
types of buffers
1 bicarbonate buffers
2 phosphate buffers
3 hemoglobin buffers
4 protein buffers
bicarbonate buffer system RXN
H2O + CO2 <> H2CO3 <> H+ + HCO3-
bicarbonate buffer system
primary defense against acid-base disorders
-most important buffer in ECF
when body fluid is acidic, H+ is high >
H+ + HCO3- > H2CO3 > H2O + CO2 > exhale CO2
when body fluid is alkaline, H+ is low >
H2CO3 > H+ HCO3-
NonVolatile Acids
lactic acid, acetoacetic acid, keto acid
the lungs can excrete ____ acid only
the lungs can excrete CARBONIC ACID only;
the CANNOT excrete nonvolatile acids