Question at position 6 In order to inhale, muscles inside the lungs contract to draw air in.TrueFalse单项选择题
A
True
B
False

Question

Question at position 6 In order to inhale, muscles inside the lungs contract to draw air in.TrueFalse

BlackTom AI · Accepted Answer

Inhalation is produced by contraction of the diaphragm and external intercostal muscles, not by muscles inside the lungs.

1. Relevant knowledge points and concepts
- The lungs themselves contain no skeletal muscles; they are elastic organs composed of airways and alveoli.
- Breathing is driven by changes in thoracic cavity volume produced by the diaphragm and intercostal muscles.
- Boyle’s law: at constant temperature, pressure and volume are inversely related (P ∝ 1/V).
- Pleural membrane and intrapleural pressure keep lungs expanded; changes in thoracic volume change intrapulmonary (alveolar) pressure relative to atmosphere, causing airflow.

2. Step-by-step reasoning
- At rest (end of exhalation) alveolar pressure ≈ atmospheric pressure (≈760 mmHg) and no net airflow.
- Contraction of the diaphragm (flattens) and external intercostals (raise ribs) increases thoracic volume.
- Increased volume lowers alveolar pressure (example: to ≈759 mmHg).
- Because alveolar pressure is now below atmospheric pressure, air flows into the lungs until pressures equilibrate.
- The lungs expand passively because they adhere to the chest wall via the pleural cavity; they do not actively “pull” air by contracting internal muscles.

3. Intermediate calculation/example
- Start: alveolar pressure = 760 mmHg. Thoracic volume increases → alveolar pressure drops slightly (e.g., to 759 mmHg). Pressure gradient 1 mmHg causes air to flow in until alveolar pressure returns to 760 mmHg.

4. Why the correct answer is correct
- The statement claims muscles inside the lungs contract to draw air in; this is false because the active force comes from thoracic muscles (diaphragm, intercostals), not from muscles within lung tissue.

5. Why the other option is incorrect
- “True” is incorrect: it misattributes the source of inspiratory force to intrapulmonary muscles. While smooth muscle in bronchioles can constrict/dilate, it does not generate the volume change needed for inhalation.

6. Conclusion
- Therefore the correct answer is False, matching the provided answer.

Question at position 6 In order to inhale, muscles inside the lungs contract to draw air in.TrueFalse单项选择题

类似问题

Continuous bubbling in the water‑seal chamber of a chest drainage system indicates?

Contraction of the respiratory diaphragm and external intercostal muscles leads to a [ Select ] rise drop in alveolar pressure, which results in [ Select ] inhalation exhalation .

What are two effective breathing exercises for improving lung function?

Which respiratory structure serves as the main airway to the lungs?

Identify the correct sequence of the parts of the respiratory system through which air passes as it enters the body.

Mr. Stuckey has a history of COPD. He experienced an exacerbation of his condition and was taken to the emergency department for treatment. What does COPD stand for?

Warm-blooded animals consume much more oxygen per body mass than cold-blooded animals. Which of the features below helps them in reducing moisture loss through breathing a lot of air?

The area in the lungs where oxygen and carbon dioxide are exchanged is called the:

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单