1. The Respiratory System
Memmler’s Structure and Function of the Human Body 9th edition
Chapter 16
The Respiratory System

2. Phases of Respiration Process of obtaining oxygen from environment and
delivering it to cells
Pulmonary ventilation
External exchange of gases
Internal exchange of gases

3. Overview of respiration.

4. Checkpoint 16-1: What are the three phases of respiration?

5. The Respiratory System
Conducts air into lungs
Nasal cavities
Pharynx
Larynx
Trachea (windpipe)
Bronchi

6. The respiratory system. (A) Overview
The respiratory system. (A) Overview. (B) Enlarged section of lung tissue showing the relationship between the alveoli (air sacs) of the lungs and the blood capillaries. (C) A transverse section through the lungs.  
Zooming In: What organ is located in the medial depression of the left lung?

7. Question: True or False
Question: True or False?: The two gases involved in the external exchange of gases that takes place in the respiratory system are CO2 and O2.

8. Answer: True: The two gases involved in the external exchange of gases that takes place in the respiratory system are CO2 and O2.

9. The Nasal Cavities Nostrils (nares) Nasal cavities Mucous membrane
Filters foreign bodies
Warms air
Moistens air
Conchae
Nasal septum
Sinuses

10. Checkpoint 16-2: What happens to air as it passes over the nasal mucosa?

11. The Pharynx Throat (pharynx) carries air to respiratory tract and food
to digestive system
Nasopharynx
Superior portion
Oropharynx
Middle portion
Laryngeal pharynx
Inferior portion

12. The Larynx Larynx (voice box) is located between the pharynx
and trachea
Cartilage framework
Thyroid cartilage (Adam’s apple)
Vocal folds (vocal cords)
Used for speech
Glottis
Epiglottis

13. The larynx.

14. The vocal cords, superior view.
ZOOMING IN • What cartilage is named for its position above the glottis?

15. The Trachea Trachea (wind pipe) conducts air between larynx and lungs
Framework of separate cartilages
Horseshoe shaped
Open at back for expansion during swallowing

16. Checkpoint 16-3: What are the scientific names for the throat, voice box, and windpipe? Checkpoint 16-4: What are the three regions of the pharynx?

17. The Bronchi Trachea divides into two primary bronchi that enter
the lungs
Hilum
Epithelial tissue lining
Pseudostratified
Cilia

18. Microscopic view of ciliated epithelium.

19. Checkpoint 16-5: The cells that line the respiratory passageways help to keep impurities out of the lungs. What feature of these cells enables them to filter impurities and move fluids?

20. Question: The air-conducting passageways of the respiratory tract are lined with what type of tissue? a. stratified squamous epithelial b. pseudostratified epithelial c. squamous epithelial

21. Answer: b. pseudostratified epithelial

22. The Lungs Mediastinum Lobes Bronchial tree Bronchioles Alveoli
Diaphragm
Pleura
Parietal pleura
Visceral pleura
Pleural space

23. Lung tissue viewed through a microscope.

24. Checkpoint 16-6: In what structures does gas exchange occur in the lung? Checkpoint 16-7: What is the name of the membrane that encloses the lung?

25. The Process of Respiration
Ventilation of lungs
Exchange of gases
Transport of gases in blood

26. Pulmonary Ventilation
Inhalation (inspiration) is active phase
Compliance
Exhalation (expiration) is passive phase
Lung capacity

27. Pulmonary ventilation.
(A)Inhalation. (B)Exhalation.  
Zooming In: What muscles are located between the ribs?

28. Checkpoint 16-8: What are the two phases of breathing
Checkpoint 16-8: What are the two phases of breathing? Which is active and which is passive?

29. Gas Exchange
Diffusion is movement of molecules from higher to lower concentration
External exchange
Gases move between alveoli and capillary blood
Internal exchange
Gases move between blood and tissues

30. Gas exchange.

31. Checkpoint 16-9: Gases move between the alveoli and the blood by the process of diffusion. What is the definition of diffusion?

32. Transport of Oxygen Most oxygen in capillary blood binds to hemoglobin
Oxygen must separate from hemoglobin to enter cells

33. Checkpoint 16-10: What substance in red blood cells carries almost all of the oxygen in the blood?

34. Transport of Carbon Dioxide
10% is dissolved in plasma and fluid in red blood cells
15% is combined with protein of hemoglobin and plasma proteins
75% dissolves in blood fluids and is converted to bicarbonate ion
First combines with water to form carbonic acid
Carbonic acid ionizes (separates) into hydrogen and bicarbonate ions
Carbonic anhydrase enzyme speeds conversion
Buffers blood to keep pH steady

35. Checkpoint 16-11: What is the main form in which carbon dioxide is carried in the blood?

36. Question: In what structure of the respiratory system does most gas exchange take place? a. bronchioles b. pleurae c. alveoli

37. Answer: c. alveoli

38. Regulation of Respiration
Fundamental respiratory pattern
Controlled by central nervous system centers
Partly in medulla (main control center), partly in pons (modifies patterns set in the medulla)
Modified by receptors detecting changes in blood chemistry

39. Nervous Control
Control center is located in medulla and pons of brain stem
Motor nerve fibers extend into spinal cord
Fibers extend through phrenic nerve to diaphragm

40. Checkpoint 16-12: What part of the brain stem sets the basic pattern of respiration? Checkpoint 16-13: What is the name of the motor nerve that controls the diaphragm?

41. Chemical Control Central chemoreceptors
Located near medullary respiratory center
Respond to raised CO2 level (hypercapnia)
Peripheral chemoreceptors
Located in neck and aortic arch
Respond to oxygen level considerably below normal

42. Checkpoint 16-14: What gas is the main chemical controller of respiration?

43. Abnormal Ventilation Hyperventilation
High oxygen level and low CO2 level (hypocapnia)
Increases blood pH
Hypoventilation
Insufficient air in alveoli
Decreases blood pH

44. Breathing Patterns Measured in breaths per minute Adults: 12 to 20
Children: 20 to 40
Infants: more than 40

45. Some Terms for Altered Breathing
Hyperpnea
Hypopnea
Tachypnea
Apnea
Dyspnea
Orthopnea
Kussmaul respiration
Cheyne-Stokes respiration

46. Question: What is the medical term for temporary cessation of breathing? a. dyspnea b. apnea c. hypopnea

47. Answer: b. apnea

48. Results of Inadequate Breathing
Cyanosis
Hypoxia
Hypoxemia
Suffocation

49. Age and the Respiratory Tract
Tissues lose elasticity, become more rigid
Decreased compliance, lung capacity
Increased susceptibility to infection
Increased incidence of emphysema
Reduced capacity for exercise

50. End of Presentation