Gas Transport Flashcards
What happens to CO2 back in the lungs?
dissolved cO2 goes down gradient back into alveoli
CO2 and H+ leave proteins as dissolved CO2 –> back into alveoli
HCO3 turns back into CO2 via carbonic acid and enters alveoli
at what PO2 is hemoglobin at least 85% saturated?
What does that mean the oxygen content of our blood is at least at?
60 mmHg
17 mL O2/dl blood
What causes a left shift in the Hb-O2 curve?
low CO2 / high pH
What are the 3 ways CO2 is found in blood?
dissolved CO2
in carbamino compounds
as HCO3 = biggest player
What is achieved btw the O2 in plasma and the Hb?
equilibrium
What is the carbonic acid-base reaction to know?
CO2 + H20 H2CO3 H+ + HCO3
How much CO2 is found in carbamino compounds?
3 ml/dl blood (7% of total)
How does the affinity of fetal Hb for oxygen compare to that of HbA?
HbF has higher affinity –> has to steal from mom’s Hb to get oxygen
How much CO2 is found in blood as HCO3?
44 mL of CO2
86% of total
What does the a-v O2 difference represent?
the amount of oxygen that was used by the tissue being perfused
What is the O2 saturation of venous blood?
What does that make your O2 content of venous blood?
75%
20.1 ml O2/dl blood x 75% = 15.2 ml O2/ dl blood
What is the solubility of CO2?
about how much CO2 is actually dissolved in blood?
6 ml CO2/ dl blood/ 100 mm Hg
actually about 2.7 ml CO2/ dl blood
(bc the Pco2 is about 45 mm hg)
What is the repiratory quotient (RQ)?
volume of co2 produced/volume of o2 cosumed = V(dot) CO2/v(dot)O2
What does a left shift in the Hb-O2 curve mean?
increase in affinity for O2
What is the CO2 made to O2 used ratio if carbohydrates are the fuel being used?
What about fats?
What is the average?
1: 1 for carbs
7: 10 for fats
200 ml CO2 produced for every 250 ml O2 consumed = 0.8 ratio avg
