Igcse Model Questions Vol1 2019 Biology Question 4

Practice essay / theory question 4 from the 2019 Igcse Model Questions Vol1 Biology examination. This question covers Respiration, Gas exchange, Respiratory regulation .

Igcse Model Questions Vol1 2019 Biology Essay / Theory

Topics: Respiration Gas exchange Respiratory regulation

Question 4 IGCSE_MODEL_QUESTIONS_VOL1 • 2019 • BIOLOGY • essay

A student records the rates of oxygen consumption (VO₂) and carbon dioxide production (VCO₂) of a volunteer at rest and while exercising on a stationary bike. The data obtained are shown in the table below. | Activity | VO₂ (mL·min⁻¹) | VCO₂ (mL·min⁻¹) | |----------|----------------|-----------------| | Rest | 250 | 200 | | Exercise | 800 | 720 | Assume the measurements are taken under steady‑state conditions.

Question Parts

( a )

Describe the main physiological changes that occur in the respiratory system when a person moves from rest to moderate exercise.

( b )

(i) Calculate the respiratory quotient (RQ) at rest and during exercise. (ii) Explain what the difference in RQ values indicates about the predominant metabolic substrate being used.

( c )

Discuss how the body regulates breathing rate to maintain blood pH within the normal range during and after exercise.

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About This Question

This is Igcse Model Questions Vol1 2019 Biology Question 4. It is one of the essay questions from the 2019 Igcse Model Questions Vol1 Biology examination.

The question covers Respiration, Gas exchange, Respiratory regulation .

View More Igcse Model Questions Vol1 2019 Biology Questions More Igcse Model Questions Vol1 Practice Questions Back to Questions

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