(b) : The ratio of the volume of CO2, released to volume of O2 absorbed in the respiratory process is termed as the respiratory ratio or Respiratory Quotient. R.Q.=‌
‌ Volume of ‌CO2‌ evolved ‌
‌ Volume of ‌O2‌ absorbed ‌
Value of R.Q. varies from one respiratory substrate to another, e.g., R.Q. of carbohydrates is equal to 1 , R.Q. of lipids and proteins are less than 1, that of organic acid is greater than 1 .