The respiratory quotient (or RQ or respiratory coefficient), is a dimensionless number used in calculations of basal metabolic rate (BMR) when estimated from carbon dioxide production. It is calculated from the ratio of carbon dioxide produced by the body to Oxygen consumed by the body. Such measurements, like measurements of oxygen uptake, are forms of indirect calorimetry. It is measured using a respirometer. The Respiratory Quotient value indicates which macronutrients are being metabolized, as different energy pathways are used for fats, carbohydrates, and proteins. A value of 0.7 indicates that lipids are being metabolized, 0.8 for proteins, and 1.0 for carbohydrates. The approximate respiratory quotient of a mixed diet is 0.8. Some of the other factors that may affect the respiratory quotient are energy balance, circulating insulin, and insulin sensitivity.
Carbohydrates: The respiratory quotient for carbohydrate Metabolism can be demonstrated by the chemical equation for oxidation of glucose:
C6H12O6 + 6 O2 → 6 CO2+ 6 H2O
Because the gas exchange in this reaction is equal, the respiratory quotient for carbohydrates is: RQ = 6 CO2 / 6 O2 = 1.0
Fats: The chemical composition of fats differs from that of carbohydrates in that fats contain considerably fewer oxygen atoms in proportion to atoms of carbon and hydrogen. The substrate utilization of palmitic acid is:
C16H32O2 + 23 O2 → 16 CO2 + 16 H2O
Thus, the RQ for palmitic acid is approximately 0.7. RQ = 16 CO2 / 23 O2 = 0.696
Proteins: The respiratory quotient for protein metabolism can be demonstrated by the chemical equation for oxidation of albumin:
The RQ for protein is approximately 0.8. RQ = 63 CO2/ 77O2 = 0.8
Due to the complexity of the various ways in which different amino acids can be metabolized, no single RQ can be assigned to the oxidation of protein in the diet; however, 0.8 is a frequently utilized estimate.
Applications
Practical applications of the respiratory quotient can be found in severe cases of chronic obstructive pulmonary disease, in which patients spend a significant amount of energy on respiratory effort. By increasing the proportion of fats in the diet, the respiratory quotient is driven down, causing a relative decrease in the amount of CO2 produced. This reduces the respiratory burden to eliminate CO2, thereby reducing the amount of energy spent on respirations.
Respiratory Quotient can be used as an indicator of over or underfeeding. Underfeeding, which forces the body to utilize fat stores, will lower the respiratory quotient while overfeeding, which causes lipogenesis, will increase it. Underfeeding is marked by a respiratory quotient below 0.85, while a respiratory quotient greater than 1.0 indicates overfeeding. This is particularly important in patients with compromised respiratory systems, as an increased respiratory quotient significantly corresponds to increased respiratory rate and decreased tidal volume, placing compromised patients at a significant risk.
Because of its role in metabolism, respiratory quotient can be used in analysis of liver function and diagnosis of liver disease. In patients suffering from liver cirrhosis, non-protein respiratory quotient (npRQ) values act as good indicators in the prediction of overall survival rate. Patients having a npRQ < 0.85 show considerably lower survival rates as compared to patients with a npRQ > 0.85.A decrease in npRQ corresponds to a decrease in glycogen storage by the liver. Similar research indicates that non-alcoholic fatty liver diseases are also accompanied by a low respiratory quotient value, and the non protein respiratory quotient value was a good indication of disease severity.
,
Respiratory quotient (RQ) is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during Respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
RQ is calculated by dividing the volume of carbon dioxide produced by the volume of oxygen consumed. The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is 0.7. The RQ of proteins is 0.8.
The RQ can be used to determine the metabolic state of an organism by calculating the respiratory quotient (RQ). The RQ is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a useful tool for determining the metabolic state of an organism, as it can be used to calculate the relative proportions of carbohydrates, fats, and proteins being metabolized.
The RQ of carbohydrates is 1.0, while the RQ of fats is
What is the respiratory quotient?
The respiratory quotient (RQ) is a ratio of the amount of carbon dioxide produced to the amount of oxygen consumed during respiration. It is a measure of how efficiently the body is using oxygen to produce energy.
What is the normal respiratory quotient?
The normal respiratory quotient for humans is 0.82. This means that for every 1 gram of glucose that is metabolized, 0.82 grams of carbon dioxide are produced and 0.18 grams of oxygen are consumed.
What are the factors that can affect the respiratory quotient?
The respiratory quotient can be affected by the type of food that is being metabolized, the level of physical activity, and the body’s metabolic rate.
What are the clinical implications of the respiratory quotient?
The respiratory quotient can be used to diagnose certain medical conditions, such as diabetes and starvation. It can also be used to monitor the effectiveness of certain treatments, such as nutritional therapy and exercise.
What are some common misconceptions about the respiratory quotient?
One common misconception about the respiratory quotient is that it is a measure of how much oxygen is being used by the body. However, the respiratory quotient is actually a measure of how efficiently the body is using oxygen to produce energy.
Another common misconception is that the respiratory quotient is always the same. However, the respiratory quotient can vary depending on the type of food that is being metabolized, the level of physical activity, and the body’s metabolic rate.
What are some Resources for Learning more about the respiratory quotient?
There are a number of resources available for learning more about the respiratory quotient. These resources include:
Textbooks on human physiology
Medical journals
Online articles
Websites of medical organizations
Sure, here are some MCQs without mentioning the topic Respiratory Quotient:
Which of the following is not a type of respiration? (A) Aerobic respiration (B) Anaerobic respiration (C) Photosynthesis (D) Fermentation-2/”>Fermentation
Which of the following is the most efficient type of respiration? (A) Aerobic respiration (B) Anaerobic respiration (C) Photosynthesis (D) Fermentation
Which of the following is the process by which Plants use sunlight to create food? (A) Aerobic respiration (B) Anaerobic respiration (C) Photosynthesis (D) Fermentation
Which of the following is the process by which cells break down glucose in the absence of oxygen? (A) Aerobic respiration (B) Anaerobic respiration (C) Photosynthesis (D) Fermentation
Which of the following is the process by which cells produce ATP in the presence of oxygen? (A) Aerobic respiration (B) Anaerobic respiration (C) Photosynthesis (D) Fermentation
Which of the following is the process by which cells produce ATP in the absence of oxygen? (A) Aerobic respiration (B) Anaerobic respiration (C) Photosynthesis (D) Fermentation
Which of the following is the main product of aerobic respiration? (A) ATP (B) CO2 (C) H2O (D) NADH
Which of the following is the main product of anaerobic respiration? (A) ATP (B) CO2 (C) H2O (D) NADH
Which of the following is the main product of photosynthesis? (A) ATP (B) CO2 (C) H2O (D) O2
Which of the following is the main product of fermentation? (A) ATP (B) CO2 (C) H2O (D) Ethanol