Question

Respiratory quotient of protein is

• A. 0.5
• B. less than 1
• C. greater than 1
• D. 1

Answer 1

The correct option is B less than 1

Respiratory quotient (RQ) is the ratio of volume of carbon dioxide evolved to volume of oxygen consumed during respiration.

RQ of proteins is about 0.9. For example: Consider albumin -

$\underset{Albumin}{C_{72}{H}_{112}{N}_{18}{O}_{22}}+77O_2⟶63C{O}_2+38H_{2}O+ATP$

$RQ=\frac{63C{O}_2}{77O_2}=0.818$ (around 0.9)

When we divide the number of $C{O}_2$ molecules evolved by the number of $O_2$ molecules consumed, we get near about 0.9. Hence, RQ for proteins is less than 1.