The Respiratory quotient of protein, carbohydrate, and fat substrates are in the order

1. a) 0.7, 1, -1
2. b) 0.9, 1, less than 1
3. c) 0, -1, 1
4. d) 1, 0.9, less than 1

Answer: b) 0.9, 1, less than 1

Explanation: Respiratory quotient is the ratio of the volume of CO2 evolved to the volume of O2 consumed. It also depends on the type of respiratory substrate. The RQ is 1 for carbohydrate substrate because of the complete oxidation. When fats are used, then RQ is less than 1. For protein substrate, the RQ ratio would be 0.9.

Also Read: Respiratory Quotient

Visit BYJU’S Biology for more exciting topics.