Respiratory System

Respiratory System

After studying this chapter, the reader should be able to:

1. Describe the primary functions of the respiratory system.

2. Identify the organs of the upper respiratory system and describe their functions.

3. Discuss the structure of the airway outside the lungs.

4. Describe the functional anatomy of the alveoli.

5. Define and compare the processes of external respiration and internal respiration.

6. Describe the major steps involved in external respiration.

7. Explain the important structures of the respiratory membrane.

8. Describe how oxygen is picked up, transported, and released in the blood.

9. Describe the factors that influence the respiration rate.

10. Identify the four distinct respiratory volumes.

Overview

The blood circulation carries oxygen from the lungs to the peripheral tissues, while simultaneously trans-porting carbon dioxide (CO₂) from these tissues back to the lungs. The respiratory system supplies the cells of the body with energy, enabling them to divide, grow, defend themselves, and maintain nor-mal structure and function. Most of this energy is obtained via aerobic mechanisms, which involve both oxygen and CO₂. Human respiratory exchange surfaces are extremely thin and delicate. They are found within the lungs, in an environment that pro-tects them and keeps them both warm and moist. As a result, diffusion occurs between air and the blood stream. The exchange surfaces of the lungs are linked via the cardiovascular system with the interstitial fluids of the body.