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 Respiratory quotient & respiratory  

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Respiratory quotient & respiratory exchange ratio , can you explain these two terms and their importance.I don.t understand them very well.


I can answer resp. exchange ratio. For each dl. of blood transport of O2 from lungs to tissues is about 5ml.,transport of CO2 from tissue to lungs is about 4ml. Therefore 80% as much CO2 is expired from the lungs as ther is O2 uptake by the lungs. This ratio of CO2 output to O2 uptake is called resp. exchange ratio. R is 1 when a person use only carbs and R is 0.7 when a person uses only fats for body metabolism. ( this is becaus the O2 combines with Hydrogen atom from fats to form H20 instead of C02.)Lastly when a person is on a normal diet consuming fat ,carbos and protein R is considered to be 0.825. R=rate of CO2 output divided by rate of O2 uptake.
Hope this helps.


Respiratory Quotient is the ratio of CO2 production to O2 utilization in metabolic reactions of body cells.

Respiratory exchange ratio is the amount of CO2 eliminated divided by the amount of O2 absorbed across the alveolar capillary membrane.

In steady state conditions , both are equal.


Thank you guys.

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