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19 Cards in this Set
- Front
- Back
What is the function of carbonic anhydrase?
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It causes the formation of H2CO3 from CO2 and H20 by a hydration reaction.
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What is the relationship of pH to excitability?
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It's a direct relationship from a pH of 7.4.
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How does the Henderson-Hasselback equation relate pH to pKa?
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pH can be thought of as a function of pKa + a corrective factor related to the concentration of the conjugate base and the undissociated acid. That is, log [A-]/[HA] (for more weak acid to be present than conjugate base, the pH has to be below the pKa).
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How does the H+ concentration compare to Na+ concentration?
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Na+ concentration is about 1 million times greater!
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What are the important acidic contributors to blood plasma?
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fatty acids, amino acids, CO2, lactic acid, and keto acids
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What are the important buffers in ECF?
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HCO3-
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What are the important buffers in the ICF?
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proteins, hemoglobin, and phosphates
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What are the important buffers in the urine?
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phosphates and ammonia
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What are some non-buffering means of controlling pH?
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respiratory response and renal response
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Why does ketosis lead to a lowered pH?
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The formation of ketone bodies leads to the formation of beta-hydroxybutyric acid and acetoacetic acid.
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Why is the Bicarbonate/CO2 buffer system effective when it's pKa is around 6.1?
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It's an open system. If there is too much acid, CO2 can be blown off. If it is too basic, HCO3- can be excreted by the kidneys.
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What are some sources of non-carbonic acid?
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protein digestion, incomplete oxidation of carbs and fats, anaerobic metabolism, incomplete fatty acid production (ketone bodies)
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What is the significance of the chloride shift in acid-base chemistry?
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The chloride shift occurs in an RBC as a cotransport mechanism by which the RBC gets rid of HCO3- to help control an acidic pH.
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What two roles does HbO2 serve in the acid-base chemistry of an RBC?
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1. It can serve as a proton acceptor for dissociated H2CO3 during times of high metabolic respiration. 2. It can serve as a CO2 acceptor during under these same circumstances. In both instances, O2 is delivered to tissue undergoing a lot of metabolic activity.
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How is CO2 carried throughout the body?
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HCO3- > CO2 >H2CO3
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When is phosphate useful as a buffer?
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In intracellular compartments.
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Other than bicarbonate, what is another extracellular buffer?
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serum albumin (of minor importance)
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How does the isohydric principle relate to acid base chemistry?
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The isohydric principle maintains that all buffering systems are in equilibrium with one another in connection with H+ allowing for a relatively wide range of constant buffering power.
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What are the components of acidotic and alkalotic events?
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A change in pH due to a primary disturbance followed by a secondary corrective response. (Responses and disturbances will be changes in pCO2 or [HCO3-] due to respiratory or metabolic causes.)
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