Respiratory System

1. Respiratory System

2. Respiratory System TortoraPage 483 • Respiratory system provides for gas exchange. • Respiration • Internal • External • Ventilation

3. Respiratory System TortoraPage 484-486 • Upper respiratory system • Nose • Pharynx • Lower respiratory system • Larynx • Trachea, etc

4. Respiratory System TortoraPage 484 • Conducting portion • Series of tubes descending in size. • Respiratory portion • Area of gas exchange. • alveoli

5. Passage of Air Through the Nose TortoraPage 485 • Functions of nose. • Warms, moistens, and filters the air. • Olfactory senses. • Resonance chamber for sounds. • Role of turbinates. • Role of mucus. • Role of Cilia

6. Pharynx TortoraPage 407 • Nasopharynx • Oropharynx • Laryngopharynx

7. Respiratory Tree TortoraPage 487 • Trachea • Supported by cartilage. • Lined with mucous membrane. • Lined by ciliated, pseudostratified columnar epithelium. • Primary bronchi • Secondary bronchi • Tertiary bronchi

8. Bronchioles TortoraPage 407 • Not supported by cartilage rings. • Smooth muscle in walls. • ANS controls diamenter of bronchiloes. • Asthma: smooth muscle spasms. • Bronchioles end in alveoli.

9. Structure of the Lungs TortoraPage 487 • Lungs lie in thoracic cavity. • Lungs surrounded by double membrane (Pleural membrane) • Secretes lubricating fluid. • Creates an air tight thoracic cavity.

10. Structure of the Alveoli TortoraPage 489 • Cup shaped pouches that make up an air sac. • Lined with simple squamous epithelium connected to a basement membrane.

12. Structure of the Alveoli TortoraPage 407 • Macrophages • Septal cells • Role of surfactant. • Alveoli are surrounded by capillaries.

13. Pulmonary Ventilation TortoraPage 490 • Air moves due to differences in pressure inside compared to outside the thoracic cavity. • Air moves from high to low pressure areas.

14. Pulmonary Ventilation: Inhalation TortoraPage 491 • Atmospheric pressure = 760 mmhg. • If thoracic air pressure equals 760 mmhg, no air will move in or out.

15. Pulmonary Ventilation: Inhalation 493 • To enlarge the thoracic cavity and create a low pressure: • Contract (pull down) the diaphragm. • External intercostal muscles contract (pulls rib cage up and out). • Alveolar air pressure drops 2 mmhg. (758 mmhg) • Air fills lungs.

16. Pulmonary Ventilation: Exhalation Wednesday 4/9/03Page 407 • Reducing the thoracic cavity size creates higher air pressures. • To create a higher thoracic cavity: • Diaphragm relaxes. • Rib cage moves down and in. • Elasticity of lungs causes them to empty • Contracting abdominal muscles force internal organs up. • Pressure rises to 762 mmhg.

17. Surfactant 489 • Phospholipid. • Produced by the septal cells. • Reduces surface tension. • The ability to easily inflate and deflate is “compliance”.

18. Pulmonary Volumes 493 • Measured using a spirometer. • Recording of volumes is called a spirogram.

19. Pulmonary Volumes 493 • Tidal volume (TV) • Inhalation or exhalation while at rest. • 500 ccm. • 350ccm reach alveoli. • Rest is in dead air space. • Minute volume of respiration: (MVR) • Tidal volume x inhalations per minute.

20. Pulmonary Volumes • Inspiratory reserve volume. (IRV) • Amount of air that can be inhaled after tidal volume. • 2500 to 3500 ccm. • Expiratory reserve. (ERV) • Amount of air tht can be exhaled after normal exhalation. • Approx. 1200 ccm.

21. Pulmonary Volumes • Residual volume (RV) • Volume of air that cannot be exhaled. • 1200 ccm. • Minimal air (vital air) • Air that clings to lung tissue after first breath.

22. Pulmonary Capacities • Inspiratory capacity (IC) • Tidal volume + inspiratory volume. • Expiratory capacity (EC) • Tidal volume + expiratory volume. • Vital capacity (VC) • Tidal volume + inspiratory reserve volume + expiratory reserve volume.

23. Pulmonary Capacities 494 • Total Lung Capacity (TLC) • Combination of: • Inspiratory volume • Tidal Volume • Expiratory volume • Reserve volume

24. Exchange of Respiratory Gases TortoraPage 495 • Oxygen and carbon dioxide move from areas of high partial pressure to areas of low partial pressure. • A gases partial pressure (p) is equal to the percentage of that gas in a mixture.

26. Transport of Respiratory Gases TortoraPage 495 • Function of blood is transport of gases. • Transports from lungs to tissues.

27. Transport of Respiratory Gases TortoraPage 495 • Transport of oxygen • 1.5% dissolves into plasma of blood. • 98.5% combines with hemoglobin to form oxyhemoglobin. Hb + O2 ------- HbO2

28. Transport of Respiratory Gases TortoraPage 497 • Transport of carbon dioxide • 7% dissolves into plasma. • 23% combines with hemoglobin to form carbaminohemoglobin. • 70% transported in plasma as carbonic acid.

29. Transport of Respiratory Gases TortoraPage 497 • Factors regarding oxygen being released by hemoglobin; • pH • Temperature

31. Transport of Respiratory Gases TortoraPage 497 • Carbon monoxide. • Binds to hemoglobin 200X more strongly than O2. CO Poisoning results because hemoglobin cannot carry oxygen if it’s bound to CO.

32. Control of Respiration TortoraPage 499 • Role of respiratory center in brain stem. • Medullary rhythmicity • Medulla oblongata • Controls breathing rhythym • Pneumotaxic Area • Pons • Limits inhalation • Apneustic Area • Lower pons • Lengthens inhalation

33. Factors that Increase Respiration TortoraPage 502 • Increase in arterial blood PCO2. • Decrease in arterial blood PO2. • Decrease in blood pressure • Increase in body temperature • Prolonged pain. • Stretching of sphincter.