im sorry bud, i didnt think you wanted to break it down this much out of your original question but the explanation you gave only allows to ponder even more.
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The difference between the amount of CO2 dissolved at venous blood pCO2 (46 mm Hg) and the amount dissolved at arterial pCO2 (40 mm Hg) is approximately 40 ml CO2 pr liter blood
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where did 40mL come from? Out of partial pressure values? Without pulling numbers out of nowhere..
standard solubility of O2 in blood = 0.03 mL O2/L/mm Hg (BRS pg.128)
standard solubility of CO2 in blood = 0.6 ml CO2/L/mm Hg (20X greater than O2)
so with 46 mmHg (venous) = 27.6 mL CO2/ L of blood
with 40 mmHg (arteries) = 16.6 mL CO2/ L of blood
difference would be 11 mL (not 40 mL)
While for partial pressure of oxygen its safer, we have to understand this would explain only the DISSOLVED CO2 which is about 5-10%. Pay much more attention to the MAJOR FORM of CO2 transport to lungs which is
HCO3- (about 80%) due to "
Cholride shift" in RBC's with the help of
carbonic anhyrdase. Other would be carbonic compounds about 15%.
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In other words, we would like the amount of air that dilutes 40 ml 100% CO2 down to 5.3% CO2 (which corresponds to 40 mm Hg). 40 ml CO2 in 800 ml air gives 5% CO2
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Huh?? down to 5.3 from what? how does that correspond to 40 mmHg? 800 ml air gives 40 ml CO2? how?
Atmosphere breakdown: 78% nitrogen, 21% oxygen, 0.03% CO2. They do teach kids its 1% because decimals havent been introduced to them yet.
.03% of 800mL (the air that we are supposed to intake) does not give 40 mL of CO2.
The percent of CO2 EXHALED is 5% and INHALED is 0.03 - 0.06%. Your calculations mixed it up maybe?
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Therefore, for each liter of blood through the lungs (giving off 40 ml CO2)...
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It does? please enlighten us.