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17 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Major homeostatic challenge is keeping ______of body fluids at appropriate level
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H+ concentration (pH)
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Diets with large amounts of ______ produce more_____than bases, which acidifies blood
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proteins
acids |
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Several mechanisms help maintain pH of arterial blood between ___and ___?
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7.35 & 7.45
these mechanisms are? |
Buffer systems, exhalation of CO2, and kidney excretion of H+
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Act to quickly temporarily bind H+
Raise pH but do not remove H+ Most consist of weak acid and salt of that acid functioning as weak base: this describes? |
buffer systems
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Most abundant buffer in ICF and blood plasma
Hemoglobin in RBCs Albumin in blood plasma Free carboxyl group acts like an acid by releasing H+ Free amino group acts as a base to combine with H+ Side chain groups on 7 of 20 amino acids also can buffer H+ this describes? |
protien buffer system
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Based on bicarbonate ion (HCO3-) acting as weak base and carbonic acid (H2CO3) acting as weak acid
HCO3- is a significant anion in both ICF and ECF Because CO2 and H2O combine to form this buffer system cannot protect against pH changes due to respiratory problems in which there is an excess or shortage of CO2 : this describes? |
Carbonic acid- bicarbonate buffer system
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Dihydrogen phosphate (H2PO4-) and monohydrogen phosphate (HPO42-)
Phosphates are major anions in ICF and minor ones in ECF Important regulator of pH in cytosol: this describes? |
Phosphate buffer system
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Increase in carbon dioxide in body fluids lowers pH of body fluids
Because H2CO3 can be eliminated by exhaling CO2 it is called a volatile acid CO2 + H2O H2CO3 H+ + HCO3- Changes in the rate and depth of breathing can alter pH of body fluids within minutes Negative feedback loop??? |
exhilation of carbon dioxide
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Metabolic reactions produce nonvolatile acids
One way to eliminate this huge load is to excrete H+ in urine In the proximal convoluted tubule, Na+ /H+ antiporters secrete H+ as they reabsorb Na+ Intercalated cells of collecting duct include proton pumps that secrete H+ into tubule fluid Urine can be up to 1000 times more acidic than blood ??? |
Kidney excretion of H+
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blood pH below 7.35?
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acidosis
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blood pH above 7.45
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alkadosis
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Major physiological effect of
Acidosis – |
depression of synaptic transmission in CNS
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Major physiological effect of Alkalosis –
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overexcitability of CNS and peripheral nerves
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complete compensation is?
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blood ph is brought within normal range
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partial compensation is?
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blood ph is still too low or high
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respiratory compensation?
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hyperventilation or hypoventilation
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reanl compensation?
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secretion of H+ and reabsorption of HCO3-
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