If the cell is usimg less oxygrn molecules than the molecules of CO2 evolved in respiration then the substrate for respiration is (1) simple sugars (2) cholesterol (3) fatty acids (4) organic acids

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Kindly refer the solution below to the asked query

The correct option is 4

The ratio of the volume of carbon dioxide produced to the volume of oxygen consumed in respiration over a period of time is called respiratory quotient. It is denoted by RQ. The value of respiratory quotient depends on the type of respiratory substrate. Its value is one for carbohydrates. 

 
When volume of CO2 evolved is more than the volume of O2 consumed, then RQ comes out to be more than 1.
When organic acids are used as respiratory substrate, then RQ is greater than 1. For example, for oxalic acid RQ= 4
 

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