Question

Respiratory quotient of Triplamithin is 0.73 and during respiration it releases 126\[C{{O}_{2}}\], Then how much\[{{O}_{2}}\] is required for its respiration?
A) 102
B) 145
C) 245
D) 173

Answer 1

Hint: Tripalmitin is a triglyceride formed from palmitic acid, a fatty acid.As different energy pathways are used for fats, carbohydrates , and proteins, the Respiratory Quotient value shows which macronutrients are being metabolised.

Complete answer:
When measured from the output of carbon dioxide, the respiratory quotient (or RQ or respiratory coefficient) is a dimensionless number used in basal metabolic rate (BMR) calculations. It is determined from the ratio of body-produced carbon dioxide to body-consumed oxygen. These measures, including oxygen uptake measurements, are types of indirect calorimetry. A respirometer is used to measure it.

The respiratory quotient is 0.7 if the metabolism consists exclusively of lipids, 0.8 for proteins and 1.0.0 for carbohydrates. However, energy intake consists of both fats and carbohydrates much of the time. A mixed diet's approximate respiratory quotient is 0.8. Some of the other variables that may influence the respiratory quotient are energy balance, circulating insulin, and sensitivity to insulin.
The ratio is the respiratory quotient (RQ):
${\text RQ} $ = $\dfrac {C{{O}_{2}}\,\,eliminated} {O_2\,\,\,absorbed}$

Where "eliminated" refers to the elimination of carbon dioxide ( \[C{{O}_{2}}\]) from the body.
In measurements of basal metabolic rate ( BMR), the respiratory quotient (RQ) is used. It is the ratio between the amount of carbon dioxide produced by the body and the volume of oxygen absorbed over a period of time by the body in respiration. It depends on the kind of respiratory substrate that is used during breathing. The RQ is about 0.7 when the respiratory substrate is fat (Tripalmitin). Where a carbohydrate is the respiratory substrate, the RQ is 1. If an organic acid is the respiratory substrate, the RQ is above 1.
Given Given

Respiratory quotient of Tripalmitin= 0.73 = 0.73
Amount of released \[C{{O}_{2}}\] = 1266
Amount of oxygen absorbed = $\dfrac{126}{0.73}$
Oxygen amount absorbed = 172.60.
The correct answer is option (D) 173.

Note:In extreme cases of chronic obstructive pulmonary disease, in which patients expend a substantial amount of energy on respiratory exertion, practical applications of the respiratory quotient can be identified. The respiratory quotient is pushed down by increasing the percentage of fats in the diet, causing a relative decrease in the amount of \[C{{O}_{2}}\] emitted. This decreases the respiratory pressure of \[C{{O}_{2}}\] elimination, thus reducing the amount of energy expended on breathing.