NEET Biology: Respiratory quotient Practice Questions
15 free multiple-choice questions on Respiratory quotient (Respiration) for NEET Biology, each with the correct answer and a step-by-step explanation. Attempt a question, then reveal the solution to check your reasoning.
Practice thousands more NEET questions in the app →Q1. The Respiratory Quotient (RQ) is defined as the ratio of the volume of oxygen consumed to the volume of carbon dioxide produced during the oxidation of a food substance. What is the unit of RQ?
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Correct answer: C — Volume/Volume
RQ is a ratio of gas volumes (or moles of O₂ to moles of CO₂), making it a dimensionless quantity or a ratio of volumes/moles.
Q2. If an organism is primarily utilizing fat for energy during aerobic respiration, what is the expected value of its Respiratory Quotient (RQ)?
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Correct answer: C — 0.7
Since the combustion of fats yields less CO₂ per unit of oxygen consumed compared to carbohydrates, the RQ value is approximately 0.7.
Q3. If an organism has an RQ value of 0.8, what type of fuel is primarily being oxidized by the body?
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Correct answer: D — Pure Proteins
An RQ value between 0.7 and 1.0 suggests a fuel source rich in protein or a mixture of fats and carbohydrates, as protein oxidation typically falls in this range.
Q4. Which statement correctly describes the relationship between RQ and the type of fuel being oxidized?
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Correct answer: C — RQ value is dependent on the chemical formula of the substance being metabolized.
The RQ value is directly dependent on the chemical composition (the ratio of C to H in the fuel) of the substance being metabolized.
Q5. For the complete oxidation of fats (lipids), what is the typical value of the Respiratory Quotient (RQ)?
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Correct answer: D — 0.7
The oxidation of fats typically yields less CO₂ relative to the O₂ consumed, resulting in an RQ value generally around 0.7.
Q6. Which of the following fuels has the lowest Respiratory Quotient (RQ) value when completely oxidized?
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Correct answer: D — Fats
Fats (lipids) yield the lowest RQ value, approximately 0.7, compared to carbohydrates (1.0) and proteins (0.8).
Q7. In a system where RQ = 1.0, what is the primary source of energy being utilized by the tissues?
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Correct answer: B — Carbohydrates
An RQ of 1.0 signifies that the oxidation process is occurring primarily through carbohydrates (like glucose).
Q8. If an organism burns pure fat for energy during respiration, the resulting Respiratory Quotient (RQ) will be approximately:
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Correct answer: B — 0.7
The oxidation of fats (lipids) involves a larger proportion of O₂ consumption relative to the CO₂ produced compared to carbohydrate oxidation. Therefore, the RQ value for fat metabolism is typically around 0.7.
Q9. Which type of fuel has an RQ value less than 1.0?
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Correct answer: B — Fats
Fuels with an RQ value less than 1.0, such as fats, produce less CO₂ per unit of O₂ consumed during their oxidation compared to carbohydrates (RQ=1.0).
Q10. The RQ value for the complete oxidation of proteins is generally higher than that for fats. What is the approximate RQ value for protein metabolism?
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Correct answer: A — 0.8
The RQ value for protein oxidation is typically around 0.8.
Q11. The RQ for the complete oxidation of carbohydrates (like glucose) is typically defined as:
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Correct answer: B — 1.0
When carbohydrates are completely oxidized, the stoichiometry results in an RQ value of exactly 1.0, meaning the volume of CO₂ produced equals the volume of O₂ consumed.
Q12. When an organism metabolizes pure carbohydrates (like glucose) for energy, what is the typical Respiratory Quotient (RQ) value observed?
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Correct answer: C — 1.0
The oxidation of carbohydrates results in the production of CO₂ and H₂O, leading to an RQ value of 1.0.
Q13. What is the Respiratory Quotient (RQ) when an organism completely metabolizes carbohydrates (like glucose)?
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Correct answer: A — 1.0
For the complete oxidation of carbohydrates (glucose), the ratio of O₂ consumed to CO₂ produced is exactly 1.0.
Q14. What is the Respiratory Quotient (RQ) defined as in terms of metabolic activity?
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Correct answer: D — The ratio of CO₂ produced to O₂ consumed during the complete oxidation of specific fuels.
The Respiratory Quotient (RQ) is defined as the ratio of the volume of carbon dioxide produced to the volume of oxygen consumed during the complete oxidation of a specific type of fuel.
Q15. The Respiratory Quotient (RQ) primarily serves what purpose in metabolism?
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Correct answer: C — To determine the type of fuel being metabolized
RQ is a crucial indicator used in biochemistry to determine the relative proportion of carbohydrate vs. fat being oxidized by the body.
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