Table of contents

1. Introduction to Anatomy & Physiology5h 43m
2. Cell Chemistry & Cell Components12h 36m
3. Energy & Cell Processes10h 6m
4. Tissues & Histology10h 3m
5. Integumentary System2h 20m
6. Bones & Skeletal Tissue2h 16m
7. The Skeletal System2h 35m
8. Joints2h 17m
9. Muscle Tissue2h 33m
10. Muscles1h 11m
11. Nervous Tissue and Nervous System1h 35m
12. The Central Nervous System1h 6m
- Introduction to the Central Nervous System
  18m
- The Cerebrum
  48m
13. The Peripheral Nervous System1h 26m
14. The Autonomic Nervous System1h 38m
15. The Special Senses2h 41m
16. The Endocrine System2h 48m
17. The Blood3h 22m
18. The Heart3h 42m
19. The Blood Vessels3h 35m
20. The Lymphatic System3h 16m
21. The Immune System14h 37m
22. The Respiratory System3h 20m
23. The Digestive System2h 5m
24. Metabolism and Nutrition4h 0m
25. The Urinary System2h 39m
26. Fluid and Electrolyte Balance, Acid Base Balance37m
27. The Reproductive System2h 5m
28. Human Development1h 21m
29. Heredity3h 32m

22. The Respiratory System

Introduction to Lung Physiology

Anatomy & Physiology

22. The Respiratory System

Introduction to Lung Physiology

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Multiple Choice

Which action would increase the volume of the thoracic cavity?

Relaxation of the diaphragm

Contraction of the diaphragm

Relaxation of the intercostal muscles

Contraction of the abdominal muscles

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Verified step by step guidance

Understand the anatomy of the thoracic cavity: The thoracic cavity is the chamber of the body that is protected by the thoracic wall (rib cage and associated muscles) and contains the lungs and heart.

Identify the role of the diaphragm: The diaphragm is a dome-shaped muscle that separates the thoracic cavity from the abdominal cavity. It plays a crucial role in respiration by contracting and relaxing to change the volume of the thoracic cavity.

Analyze the effect of diaphragm contraction: When the diaphragm contracts, it moves downward, increasing the vertical dimension of the thoracic cavity. This action increases the volume of the thoracic cavity, creating a negative pressure that draws air into the lungs.

Consider the role of intercostal muscles: The intercostal muscles, located between the ribs, also assist in changing the volume of the thoracic cavity. When they contract, they elevate the ribs, further increasing the thoracic volume.

Evaluate the effect of abdominal muscle contraction: Contraction of the abdominal muscles typically decreases the volume of the thoracic cavity by pushing the diaphragm upward, which is opposite to the action needed to increase thoracic volume.