Question

RQ of protein is
A. 0.7
B. 1.0
C. 0.9
D. more than one

Answer 1

Hint:- RQ is a respiratory quotient whose value is calculated by dividing the volume of carbon dioxide evolved to the volume of oxygen consumed and its value depends on respiratory substrate.

Complete step-by-step solution:-First of all, you should know what RQ is to solve this question. RQ is the respiratory quotient which is the ratio of the volume of carbon dioxide produced by the body to that of the volume of oxygen consumed by the body in respiration. This calculation is used in basal metabolic rate and this RQ value varies according to the type of respiratory substrate during respiration.
If we look at options now, Option A is 0.7. RQ is 0.7 when the respiratory substrate is fat. But in the question, respiratory substrate for protein is asked and this cannot be the respiratory quotient for protein and therefore this option is incorrect and it gets eliminated.
Moving to option B which is 1.0. RQ is 1.0 when the respiratory substrate is carbohydrate. But in the question, respiratory substrate for protein is asked and this cannot be the respiratory quotient for protein and therefore this option is incorrect and it gets eliminated.
Moving to option C which is 0.9. RQ is 0.9 when respiratory substrate is protein and therefore this option is correct one as in the option respirator substrate for protein is asked.
Last option D is more than one. RQ is more than one when the respiratory substrate is organic acid. But in the question, respiratory substrate for protein is asked and this cannot be the respiratory quotient for protein and therefore this option is incorrect and it gets eliminated.
Thus, the correct answer is option C which is 0.9

Note:- Since respiratory quotient's value is dependent on the respiratory substrate, therefore RQ value is different for each substrate, for example, RQ for fat is 0.7, RQ for carbohydrate is 1.0, RQ for protein is 0.9 and RQ for organic acid is more than 1. In the question, RQ for protein is asked and thus 0.9 is the correct RQ value for protein.