Lec 5 - Acid-base balance

Strong acids _____ dissociate at ___ pH

completely, any

Weak acids ____ dissociate at ___ pH

partially, certain

Healthy pH range for animal blood

7.4-7.3

Healthy pH range for cells w/in tissues

7.2-4.7 (depends on location)

What are the two buffers that help maintain desired pH

intrinsic and extrinsic

Define intrinsic pH buffer (Bintrinsic)

intra/extracellular weak acids and bases (phosphates, amino acids)

Define extrinsic pH buffer (BHCO3-)

hydration abundance of CO2 -> deprotonation of carbonic acid -> HCO3- (bicarbonate buffer system)

pKa is when weak acid is ____ dissociated

half

____ acids can act to _____ proton or ______ serving as a buffer

Weak, give off, accept

Proton motor force is key for _________ in the cell

converting energy

Total Buffer Capacity = ______ + ______

Bintrinisc, BHCO3-

_______ catalyzes the spontaneous rxn for carbonic acid/bicarbonate buffer system (Hint: CA)

carbonic anhydrase

____________ system is the largest buffering capacity in the body

carbonic acid/bicarbonate buffer

#1 source of weak bases (HCO3)

parietal cells from stomach

#1 source of acid

metabolism (volatile acid) via oxidation of glucose and fatty acids from CO2

2nd source of acid

fixed (non volatile acid), H2SO4 from sulfur containing amino acids

Buffers _____ change in pH

resist

Buffers are made up of _______ + ________

weak acid, its conjugate base

The H-H equation solves _________________ in a biolgoical system

concentration of acids

homeostasis of the pH is regulated through formation of ____

H2CO3 (carbonic acid)

Intrinsic pH buffer is ____ buffer

phospate

What are the 3 pKas of phosphate

2.1, 7.2, and 12.3

Which of the 3 pKas of phosphate is for buffering

7.2

ionizable amino acids, RBC, plasma proteins all serve as what?

intrinsic pH buffer

high sulfate and phosphate in environment leads to what

acidosis

ingestion of fruits leads to what due to citrate

alkalosis

Excess H2CO3 (carbonic acid) gets converted to __ and _ in the lungs

H2O, CO2

For the kidneys role in controlling acidosis, ___ gets reabsorbed into the blood, and ___ & ___ get secreted into urine

HCO3, H+ & NH4+

When the kidneys fail to modulate HCO3- excretion what could happen

metabolic alkalosis

Inability of the kidney to generate NH3 leads to what

acidosis

As H+ gets eliminated in urine, what needs to simultaneously happen

excretion of cations to maintain electrical neutrality