Question

Define RQ. What is RQ value for fats?

Answer 1

Respiratory Quotient ( R. Q) is the ratio of the volume of carbon dioxide release to the volume of oxygen taken in respiration in the given period of time at standard temperature and pressure.

RQof fats- When fats are respiratory substrates, during germination of seeds, the fats are hydrolysed to fatty acids and glycerol. The complete oxidation of glycerol results in the RQ of 0.86. The fatty acids, being poorer in oxygen, require more O2 for complete oxidation as compared to CO2. Therefore, O2 absorption is more and CO2 liberation and RQ becomes less than unity. For example-

RQ is 0.7 during oxidative breakdown of glycerol palmitate-

$2C_{51}{H}_{98}{O}_6+145O_2\to 102C{O}_2+98H_{2}O+Energy$

RQ= Vol. of CO2\ Vol.of O= 102\145= 0.7

The RQ of fats is mostly less than 1.