The respiratory quotient when catabolizing carbohydrates is

The respiratory quotient when catabolizing carbohydrates is ______ and ______ when catabolizing fats.

(a) 1.0, 0.8

(b) 1.0, 0.7

(c) 0. 7, 1.0

(d) 1.0, 1.0

(e) 0.7, 0.7

Solution

Answer: (b) 1.0, 0.7

Explanation:

Respiratory Quotient (RQ) is the ratio of the volume of CO₂ produced to the volume of O₂ consumed per unit time, in the steady state. This is different from the ‘Respiratory Exchange Ratio’ (R or RER), which quantifies the same ratio at any point in time, not only at equilibrium.

RQ = V ­produced CO₂ / V consumed O₂

RQ of carbohydrate is 1.0, proteins is 0.8-0.9 and for fat 0.7.