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

1. Introduction to Anatomy & Physiology

Introduction to Organ Systems

Anatomy & Physiology

1. Introduction to Anatomy & Physiology

Introduction to Organ Systems

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Multiple Choice

Air moves out of the lungs when the pressure inside the lungs is ________.

equal to atmospheric pressure

less than atmospheric pressure

greater than atmospheric pressure

lower than the pressure in the alveoli

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Verified step by step guidance

Understand the concept of pressure gradients: Air moves in and out of the lungs based on pressure differences between the lungs and the atmosphere. This is governed by Boyle's Law, which states that pressure and volume are inversely related.

Recognize the role of the diaphragm and intercostal muscles: During exhalation, the diaphragm relaxes and moves upward, while the intercostal muscles relax, reducing the volume of the thoracic cavity.

Relate volume changes to pressure changes: As the thoracic cavity volume decreases, the pressure inside the lungs (intrapulmonary pressure) increases relative to atmospheric pressure.

Apply the principle of air movement: Air moves from areas of higher pressure to areas of lower pressure. During exhalation, the increased intrapulmonary pressure forces air out of the lungs into the atmosphere.

Conclude the relationship: Air moves out of the lungs when the pressure inside the lungs is greater than atmospheric pressure, as this creates the necessary pressure gradient for exhalation.