1. PowerPoint ® Lecture Slides prepared by Barbara Heard, Atlantic Cape Community College C H A P T E R © 2013 Pearson Education, Inc.© Annie Leibovitz/Contact Press Images The Respiratory System: Part A 22

2. © 2013 Pearson Education, Inc.

3. The Respiratory System Major function-respiration –Supply body with O 2 for cellular respiration; dispose of CO 2, a waste product of cellular respiration –Its four processes involve both respiratory and circulatory systems Also functions in olfaction and speech

4. © 2013 Pearson Education, Inc. Pulmonary ventilation (breathing)- movement of air into and out of lungs External respiration-O 2 and CO 2 exchange between lungs and blood Transport-O 2 and CO 2 in blood Internal respiration-O 2 and CO 2 exchange between systemic blood vessels and tissues Respiratory system Circulatory system Processes of Respiration

5. © 2013 Pearson Education, Inc. Respiratory System: Functional Anatomy Major organs –Nose, nasal cavity, and paranasal sinuses –Pharynx –Larynx –Trachea –Bronchi and their branches –Lungs and alveoli

6. © 2013 Pearson Education, Inc. Figure 22.1 The major respiratory organs in relation to surrounding structures. Nasal cavity Nostril Larynx Trachea Carina of trachea Right main (primary) bronchus Right lung Oral cavity Pharynx Left main (primary) bronchus Left lung Diaphragm

7. © 2013 Pearson Education, Inc. The Nose Functions –Provides an airway for respiration –Moistens and warms entering air –Filters and cleans inspired air –Serves as resonating chamber for speech –Houses olfactory receptors

8. © 2013 Pearson Education, Inc. Nasal Cavity Nasal vestibule-nasal cavity superior to nostrils –Vibrissae (hairs) filter coarse particles from inspired air Rest of nasal cavity lined with mucous membranes –Olfactory mucosa –Respiratory mucosa

9. © 2013 Pearson Education, Inc. Nasal Cavity Respiratory mucosa –Mucous and serous secretions contain lysozyme and defensins –Cilia move contaminated mucus posteriorly to throat

10. © 2013 Pearson Education, Inc. Figure 22.3b The upper respiratory tract. Pharyngeal tonsil Oropharynx Cribriform plate of ethmoid bone Sphenoidal sinus Posterior nasal aperture Nasopharynx Opening of pharyngotympanic tube Uvula Palatine tonsil Isthmus of the fauces Laryngopharynx Esophagus Trachea Frontal sinus Nasal cavity Nasal conchae (superior, middle and inferior) Nasal meatuses (superior, middle, and inferior) Nasal vestibule Nostril Hard palate Soft palate Tongue Lingual tonsil Hyoid bone Larynx Epiglottis Vestibular fold Thyroid cartilage Vocal fold Cricoid cartilage Thyroid gland Illustration

11. © 2013 Pearson Education, Inc. Figure 22.3a The upper respiratory tract. Olfactory epithelium Mucosa of pharynx Tubal tonsil Pharyngotympanic (auditory) tube Nasopharynx Olfactory nerves Superior nasal concha and superior nasal meatus Middle nasal concha and middle nasal meatus Inferior nasal concha and inferior nasal meatus Hard palate Soft palate Uvula Photograph

12. © 2013 Pearson Education, Inc. Functions of the Nasal Mucosa and Conchae During inhalation, conchae and nasal mucosa –Filter, heat, and moisten air During exhalation these structures –Reclaim heat and moisture

13. © 2013 Pearson Education, Inc. Paranasal Sinuses In frontal, sphenoid, ethmoid, and maxillary bones Lighten skull; secrete mucus; help to warm and moisten air

14. © 2013 Pearson Education, Inc. Homeostatic Imbalance Rhinitis –Inflammation of nasal mucosa –Nasal mucosa continuous with mucosa of respiratory tract  spreads from nose  throat  chest –Spreads to tear ducts and paranasal sinuses causing Blocked sinus passageways  air absorbed  vacuum  sinus headache

15. © 2013 Pearson Education, Inc. Pharynx Muscular tube –Connects nasal cavity and mouth to larynx and esophagus –Composed of skeletal muscle Three regions –Nasopharynx –Oropharynx –Laryngopharynx

16. © 2013 Pearson Education, Inc. Figure 22.3c The upper respiratory tract. Nasopharynx Oropharynx Laryngopharynx Regions of the pharynx Pharynx

17. © 2013 Pearson Education, Inc. Nasopharynx Air passageway posterior to nasal cavity Lining - pseudostratified columnar epithelium Soft palate and uvula close nasopharynx during swallowing Pharyngeal tonsil (adenoids) on posterior wall Pharyngotympanic (auditory) tubes drain and equalize pressure in middle ear; open into lateral walls

18. © 2013 Pearson Education, Inc. Oropharynx Passageway for food and air from level of soft palate to epiglottis Lining of stratified squamous epithelium Isthmus of fauces-opening to oral cavity Palatine tonsils-in lateral walls of fauces Lingual tonsil-on posterior surface of tongue

19. © 2013 Pearson Education, Inc. Laryngopharynx Passageway for food and air Posterior to upright epiglottis Extends to larynx, where continuous with esophagus Lined with stratified squamous epithelium

20. © 2013 Pearson Education, Inc. Figure 22.3b The upper respiratory tract. Pharyngeal tonsil Oropharynx Cribriform plate of ethmoid bone Sphenoidal sinus Posterior nasal aperture Nasopharynx Opening of pharyngotympanic tube Uvula Palatine tonsil Isthmus of the fauces Laryngopharynx Esophagus Trachea Frontal sinus Nasal cavity Nasal conchae (superior, middle and inferior) Nasal meatuses (superior, middle, and inferior) Nasal vestibule Nostril Hard palate Soft palate Tongue Lingual tonsil Hyoid bone Larynx Epiglottis Vestibular fold Thyroid cartilage Vocal fold Cricoid cartilage Thyroid gland Illustration

21. © 2013 Pearson Education, Inc. Larynx Attaches to hyoid bone; opens into laryngopharynx; continuous with trachea Functions –Provides patent airway –Routes air and food into proper channels –Voice production Houses vocal folds

22. © 2013 Pearson Education, Inc. Figure 22.4a The larynx. Body of hyoid bone Thyroid cartilage Laryngeal prominence (Adam’s apple) Cricothyroid ligament Cricotracheal ligament Epiglottis Thyrohyoid membrane Cricoid cartilage Tracheal cartilages Anterior superficial view

23. © 2013 Pearson Education, Inc. Figure 22.4b The larynx. Epiglottis Thyrohyoid membrane Cuneiform cartilage Corniculate cartilage Arytenoid cartilage Arytenoid muscles Cricoid cartilage Tracheal cartilages Body of hyoid bone Thyrohyoid membrane Fatty pad Vestibular fold (false vocal cord) Thyroid cartilage Vocal fold (true vocal cord) Cricothyroid ligament Cricotracheal ligament Sagittal view; anterior surface to the right

24. © 2013 Pearson Education, Inc. Figure 22.4c The larynx. Epiglottis Hyoid bone Thyroid cartilage Lateral thyrohyoid membrane Corniculate cartilage Arytenoid cartilage Glottis Cricoid cartilage Tracheal cartilages Photograph of cartilaginous framework of the larynx, posterior view

25. © 2013 Pearson Education, Inc. Figure 22.4d The larynx. Posterior cricoarytenoid muscle on cricoid cartilage Trachea Corniculate cartilage Laryngeal inlet Epiglottis Photograph of posterior aspect(d)

26. © 2013 Pearson Education, Inc. Figure 22.5 Movements of the vocal folds. Vestibular fold (false vocal cord) Base of tongue Epiglottis Vocal fold (true vocal cord) Glottis Inner lining of trachea Cuneiform cartilage Corniculate cartilage Vocal folds in closed position; closed glottis Vocal folds in open position; open glottis

27. © 2013 Pearson Education, Inc. Trachea Windpipe–from larynx into mediastinum Wall composed of three layers –Mucosa-ciliated pseudostratified epithelium with goblet cells –Submucosa-connective tissue with seromucous glands –Adventitia-outermost layer made of connective tissue; encases C-shaped rings of hyaline cartilage

28. © 2013 Pearson Education, Inc. Figure 22.6b Tissue composition of the tracheal wall. Goblet cell Pseudostratified ciliated columnar epithelium Lamina propria (connective tissue) Mucosa Submucosa Hyaline cartilage Seromucous gland In submucosa Photomicrograph of the tracheal wall (320 x )

29. © 2013 Pearson Education, Inc. Figure 22.6c Tissue composition of the tracheal wall. Scanning electron micrograph of cilia in the trachea (2500 x )

30. © 2013 Pearson Education, Inc. Conducting Zone Structures Trachea  right and left main (primary) bronchi

31. © 2013 Pearson Education, Inc. Conducting Zone Structures Branches become smaller and smaller  –Bronchioles-less than 1 mm in diameter –Terminal bronchioles-smallest-less than 0.5 mm diameter

32. © 2013 Pearson Education, Inc. Figure 22.7 Conducting zone passages. Superior lobe of right lung Middle lobe of right lung Inferior lobe of right lung Trachea Superior lobe of left lung Left main (primary) bronchus Lobar (secondary) bronchus Segmental (tertiary) bronchus Inferior lobe of left lung

33. © 2013 Pearson Education, Inc. Conducting Zone Structures From bronchi through bronchioles, structural changes occur –Cartilage rings become irregular plates; in bronchioles elastic fibers replace cartilage –Epithelium changes from pseudostratified columnar to cuboidal; cilia and goblet cells become sparse –Relative amount of smooth muscle increases Allows constriction

34. © 2013 Pearson Education, Inc. Respiratory Zone Begins as terminal bronchioles  respiratory bronchioles  alveolar ducts  alveolar sacs –Alveolar sacs contain clusters of alveoli ~300 million alveoli make up most of lung volume Sites of gas exchange

35. © 2013 Pearson Education, Inc. Figure 22.8a Respiratory zone structures. Alveolar duct Respiratory bronchioles Terminal bronchiole Alveoli Alveolar duct Alveolar sac

36. © 2013 Pearson Education, Inc. Figure 22.8b Respiratory zone structures. Respiratory bronchiole Alveolar duct Alveoli Alveolar sac Alveolar pores

37. © 2013 Pearson Education, Inc. Respiratory Membrane Alveolar and capillary walls and their fused basement membranes –~0.5-µm-thick; gas exchange across membrane by simple diffusion Alveolar walls –Single layer of squamous epithelium (type I alveolar cells) Scattered cuboidal type II alveolar cells secrete surfactant and antimicrobial proteins

38. © 2013 Pearson Education, Inc. Figure 22.9a Alveoli and the respiratory membrane. Terminal bronchiole Respiratory bronchiole Smooth muscle Elastic fibers Alveolus Capillaries Diagrammatic view of capillary-alveoli relationships

39. © 2013 Pearson Education, Inc. Figure 22.9b Alveoli and the respiratory membrane. Scanning electron micrograph of pulmonary capillary casts (70 x )

40. © 2013 Pearson Education, Inc. Alveoli Surrounded by fine elastic fibers and pulmonary capillaries Alveolar pores connect adjacent alveoli Equalize air pressure throughout lung Alveolar macrophages keep alveolar surfaces sterile –2 million dead macrophages/hour carried by cilia  throat  swallowed

41. © 2013 Pearson Education, Inc. Figure 22.9c Alveoli and the respiratory membrane. Red blood cell in capillary Alveoli (gas-filled air spaces) Type II alveolar cell Type I alveolar cell Capillary Macrophage Endothelial cell nucleus Respiratory membrane Alveolar epithelium Fused basement membranes of alveolar epithelium and capillary endothelium Capillary endothelium Capillary Alveolus Nucleus of type I alveolar cell Alveolar pores Red blood cell Alveolus Detailed anatomy of the respiratory membrane

42. © 2013 Pearson Education, Inc. Figure 22.10c Anatomical relationships of organs in the thoracic cavity. Transverse section through the thorax, viewed from above. Lungs, pleural membranes, and major organs in the mediastinum are shown. Posterior Parietal pleura Visceral pleura Pleural cavity Pericardial membranes Sternum Vertebra Esophagus (in mediastinum) Root of lung at hilum Left main bronchus Left pulmonary artery Left pulmonary vein Thoracic wall Heart (in mediastinum) Anterior mediastinum Anterior Left lung Pulmonary trunk Right lung

43. © 2013 Pearson Education, Inc. Figure 22.10a Anatomical relationships of organs in the thoracic cavity. Trachea Thymus Apex of lung Right inferior lobe Horizontal fissure Right superior lobe Oblique fissure Right middle lobe Heart (in mediastinum) Diaphragm Base of lung Intercostal muscle Rib Parietal pleura Pleural cavity Visceral pleura Left superior lobe Oblique fissure Left inferior lobe Cardiac notch Anterior view. The lungs flank mediastinal structures laterally. Lung

44. © 2013 Pearson Education, Inc. Figure 22.10b Anatomical relationships of organs in the thoracic cavity. Apex of lung Pulmonary artery Left main bronchus Pulmonary vein Cardiac impression Oblique fissure Lobules Photograph of medial view of the left lung. Left superior lobe Oblique fissure Left inferior lobe Hilum of lung Aortic impression

45. © 2013 Pearson Education, Inc. Figure 22.11 A cast of the bronchial tree. Right lungLeft lung Left superior lobe (4 segments) Left inferior lobe (5 segments) Right inferior lobe (5 segments) Right middle lobe (2 segments) Right superior lobe (3 segments)

46. © 2013 Pearson Education, Inc. Blood Supply Pulmonary circulation (low pressure, high volume) –Pulmonary arteries deliver systemic venous blood to lungs for oxygenation Branch profusely; feed into pulmonary capillary networks –Pulmonary veins carry oxygenated blood from respiratory zones to heart

47. © 2013 Pearson Education, Inc. Figure 22.10c Anatomical relationships of organs in the thoracic cavity. Transverse section through the thorax, viewed from above. Lungs, pleural membranes, and major organs in the mediastinum are shown. Posterior Parietal pleura Visceral pleura Pleural cavity Pericardial membranes Sternum Vertebra Esophagus (in mediastinum) Root of lung at hilum Left main bronchus Left pulmonary artery Left pulmonary vein Thoracic wall Heart (in mediastinum) Anterior mediastinum Anterior Left lung Pulmonary trunk Right lung

48. © 2013 Pearson Education, Inc. Mechanics of Breathing Pulmonary ventilation consists of two phases –Inspiration-gases flow into lungs –Expiration-gases exit lungs

49. © 2013 Pearson Education, Inc. Figure 22.12 Intrapulmonary and intrapleural pressure relationships. Atmospheric pressure (P atm ) 0 mm Hg (760 mm Hg) Thoracic wall Parietal pleura Visceral pleura Pleural cavity Transpulmonary pressure 4 mm Hg (the difference between 0 mm Hg and −4 mm Hg) Intrapleural pressure (P ip ) −4 mm Hg (756 mm Hg) Intrapulmonary pressure (P pul ) 0 mm Hg (760 mm Hg) Diaphragm Lung 0 – 4

50. © 2013 Pearson Education, Inc. Homeostatic Imbalance Atelectasis (lung collapse) due to –Plugged bronchioles  collapse of alveoli –Pneumothorax-air in pleural cavity From either wound in parietal or rupture of visceral pleura Treated by removing air with chest tubes; pleurae heal  lung reinflates

51. © 2013 Pearson Education, Inc. Figure 22.13 Changes in thoracic volume and sequence of events during inspiration and expiration. (1 of 2) Slide 1 Inspiratory muscles contract (diaphragm descends; rib cage rises). Thoracic cavity volume increases. Lungs are stretched; intrapulmonary volume increases. Intrapulmonary pressure drops (to –1 mm Hg). Air (gases) flows into lungs down its pressure gradient until intrapulmonary pressure is 0 (equal to atmospheric pressure). Inspiration Sequence of events Changes in anterior-posterior and superior-inferior dimensions Changes in lateral dimensions (superior view) 1 2 3 4 5 Diaphragm moves inferiorly during contraction. Ribs are elevated and sternum flares as external intercostals contract. External intercostals contract.

52. © 2013 Pearson Education, Inc. Expiration Quiet expiration normally passive process –Inspiratory muscles relax –Thoracic cavity volume decreases –Elastic lungs recoil and intrapulmonary volume decreases  pressure increases (P pul rises to +1 mm Hg)  –Air flows out of lungs down its pressure gradient until P pul = 0 Note: forced expiration-active process; uses abdominal (oblique and transverse) and internal intercostal muscles

53. © 2013 Pearson Education, Inc. Figure 22.13 Changes in thoracic volume and sequence of events during inspiration and expiration. (2 of 2) Slide 1 1 Expiration Sequence of events Changes in anterior-posterior and superior-inferior dimensions Changes in lateral dimensions (superior view) 2 3 4 5 Diaphragm moves superiorly as it relaxes. Ribs and sternum are depressed as external intercostals relax. External intercostals relax. Inspiratory muscles relax (diaphragm rises; rib cage descends due to recoil of costal cartilages). Thoracic cavity volume decreases. Elastic lungs recoil passively; intrapulmonary Volume decreases. Intrapulmonary pressure rises (to +1 mm Hg). Air (gases) flows out of lungs down its pressure gradient until intrapulmonary pressure is 0.

54. © 2013 Pearson Education, Inc. Homeostatic Imbalance As airway resistance rises, breathing movements become more strenuous Severe constriction or obstruction of bronchioles –Can prevent life-sustaining ventilation –Can occur during acute asthma attacks; stops ventilation Epinephrine dilates bronchioles, reduces air resistance

55. © 2013 Pearson Education, Inc. Alveolar Surface Tension Surfactant –Detergent-like lipid and protein complex produced by type II alveolar cells –Reduces surface tension of alveolar fluid and discourages alveolar collapse –Insufficient quantity in premature infants causes infant respiratory distress syndrome  alveoli collapse after each breath