1. The Respiratory System
Chapter 23, part 1
The Respiratory System

2. SECTION 23-1 The Respiratory System: An Introduction

3. Learning Objectives
Describe the primary functions of the respiratory system
Identify the organs of the respiratory system and describe their functions
Define and compare the processes of external and internal respiration

4. Learning Objectives
Summarize the physical principles governing the movement of air into the lungs and the diffusion of gases into the blood
Explain the important structural features of the respiratory membrane
Describe how oxygen and carbon dioxide are picked up, transported and released in the blood

5. Functions of the respiratory system
Gas exchange between air and circulating blood
Moving air from the exchange surface of the lungs
Protection of respiratory surfaces
Production of sound
Provision for olfactory sensations

6. Organization of the respiratory system
Upper respiratory system
Nose, nasal cavity, paranasal sinuses, pharynx
Lower respiratory system
Larynx, trachea, bronchi, bronchioles, alveoli

7. Figure 23.1 The Components of the Respiratory System

8. The Respiratory tract
Conducting passageways carrying air to and from the alveoli
Upper respiratory passages filter and humidify incoming air
Lower passageways include delicate conduction passages and alveolar exchange surfaces

9. Respiratory Mucosa
Respiratory epithelium and underlying connective tissue
Respiratory membrane, supported by lamina propria, changes along tract
Lines conducting portion of respiratory tract
Protected from contamination by respiratory defense system

10. Figure 23.2 The Respiratory Epithelium of the Nasal Cavity and Conducting System

11. SECTION 23-2 The Upper Respiratory System

12. The nose and nasal cavity consists of:
External nares
Nasal cavity
Vestibule
Superior, middle and inferior meatuses
Hard and soft palates
Internal nares
Nasal mucosa

13. Figure 23.3 The Nose, Nasal Cavity, and Pharynx
Figure 23.3a, b

14. Figure 23.3 The Nose, Nasal Cavity, and Pharynx
Figure 23.3c

15. The pharynx Shared by the digestive and respiratory systems
Divided into three sections:
Nasopharynx – superior portion
Oropharynx – continuous with the oral cavity
Laryngopharynx – between the hyoid bone and the esophagus

16. SECTION The Larynx

17. The larynx Air passes through the glottis on the way to the lungs
Larynx protects the glottis
Cartilages of the larynx
Three large cartilages
Thyroid, cricoid, and epiglottis
Paired cartilages
Arytenoids, corniculate, and cuneiform

18. Folds of the larynx
Inelastic vestibular folds
Delicate vocal folds

19. Figure 23.4 The Anatomy of the Larynx

20. Sound production
Air passing through the glottis vibrates the vocal folds producing sound waves
Pitch depends on conditions of vocal folds
Diameter
Length
Tension

21. Figure The Glottis
Figure 23.5a, b

22. The laryngeal musculature
Muscles of the neck and pharynx position and stabilize the larynx
When swallowing,these muscles
Elevate the larynx
Bend the epiglottis over the glottis
Intrinsic muscles control tension on the vocal folds and open the glottis

23. SECTION 23-4 The Trachea and Primary Bronchi

24. The trachea
Extends from the sixth cervical vertebra to the fifth thoracic vertebra
A tough, flexible tube running from the larynx to the bronchi
Held open by C-shaped tracheal cartilages in submucosa
Mucosa is similar to the nasopharynx

25. Figure 23.6 The Anatomy of the Trachea
Figure 23.6a, b

26. Figure 23.6 The Anatomy of the Trachea
Figure 23.6c

27. The primary bronchi
Trachea branches in the mediastinum into right and left bronchi
Bronchi enter the lungs at the hilus
Root = the connective tissue mass including:
Bronchus
Pulmonary vessels
Nerves