Chapter 18, Problem 1RQ

Summary Introduction

Introduction:

A high amount of oxygen is required during heavy exercise for body cells and organs to function properly. Heavy exercise causes the blood pressure to increase. This provides the strength to the muscles and also improves the pumping ability of the blood by the heart to lungs and other body parts.

Answer to Problem 1RQ

Correct answer:

20 fold.

Explanation of Solution

Explanation for the correct answer:

Option (b) is, ‘20 fold’. The cardiopulmonary system’s components may get stressed to their limits during heavy exercise. The alveolar ventilation increases 20 fold along with oxygen diffusion capacity, blood flow in muscles, consumption of oxygen, and production of heat. Hence, option (b) is correct.

Explanation for the incorrect answer:

Option (a) is, ‘10 fol0d’. The alveolar ventilation increase is coupled with oxygen diffusion capacity, muscle blood flow, oxygen consumption, and heat production. The value of alveolar ventilation increases 20 fold. So, it is an incorrect option.

Option (c) is, ‘30 fold’. The amount of gas exchange in an adult is 6 L (liters)/ min during normal quiet breathing. The alveolar ventilation increases 20 fold during strenuous exercise. So, it is an incorrect option.

Option (d) is, ‘40 fold’. The strenuous exercise increases the alveolar ventilation 20 fold. So, it is an incorrect option.

Hence, options (a), (c), and (d) are incorrect.

Conclusion

Therefore, it can be concluded that the alveolar ventilation increases 20 fold during heavy exercise. An adult interchanges approximately 6 L of the gas per minute during the normal quiet breathing.