Acid-Base I: Regulation of Balance Flashcards
Does metabolically generated CO2 have an impact on acid-base balance?
No, because this CO2 is normally eliminated by the lungs.
What is the difference between a volatile and nonvolatile acid?
A volatile acid has the potential to form H+ upon hydration (like CO2), while a nonvolatile acid is not derived from the hydration of CO2 (like lactic acid).
The kidney and lungs operate on the _____ space and rid the body of volatile and nonvolatile acids __________ to their production.
plasma; in proportion
Do the lungs or kidneys have a greater capacity to remove acidity?
the lungs (190x greater capacity)
Why can acute changes in arterial plasma pH be tolerated?
because rapid changes in extracellular pH do not greatly affect intracellular pH (a direct consequence of slow proton diffusion across cell membranes)
Do meat-rich diets or vegetarian diets produce more nonvolatile acids?
meat-rich diets
In a healthy individual consuming a typical Western diet, how much net addition of acid is there to the body?
~50-100 mEq/day
What happens if fixed acids are not removed from the body, like in pathological states?
metabolic acidosis may result
Do nonvolatile acids circulate through the body?
No! They are immediately neutralized by HCO3- in the ECF.
What would happen if our HCO3- were not replenished?
nonvolatile acids in the body would deplete the ECF of bicarbonate in roughly 5 days
What makes a good buffer?
weak acids with pKa values near environmental pH
Define a conjugate acid and a conjugate base.
- CA: an undissociated acid that has the potential to donate a proton to the solution
- CB: a negatively charged anion that has the potential to accept a proton
Where is the phosphate buffer system most relevant?
within the kidney, where the components of the system are higher due to counter-current multiplication; concentrations of buffer pair components are low in the plasma, thus making it a rather unimportant EC buffer
What makes Hb a good buffer?
the imidazole group of the histidine residues, which provides the bulk of protein binding sites on Hb
The kidneys regulate RNAE to ____________.
match NEAP and replenish HCO3- lost by nonvolatile acid neutralization
