1. Chapter 14 The Respiratory System Week 4 Hs 130

2. Agenda Questions from Last Week Review Chapter 14
Question and Answer Session
Answer any Questions.

3. STRUCTURAL PLAN
Basic plan of respiratory system would be similar to an inverted tree if it were hollow; leaves of the tree would be comparable to alveoli, with the microscopic sacs enclosed by networks of capillaries (Figure 14-1)
Passive transport process of diffusion is responsible for the exchange of gases that occur during respiration.

5. RESPIRATORY TRACTS What comprises the: Upper respiratory tract—
Lower respiratory tract—

6. Answer-RESPIRATORY TRACTS
Upper respiratory tract—nose, pharynx, and larynx
Lower respiratory tract—trachea, bronchial tree, and lungs

7. RESPIRATORY MUCOSA
Specialized membrane that lines the air distribution tubes in the respiratory tree (Figure 14-2)
More than 125 mL of mucus produced each day forms a “mucous blanket” over much of the respiratory mucosa
Mucus serves as an air purification mechanism by trapping inspired irritants such as dust and pollen
Cilia on mucosal cells beat in only one direction, moving mucus upward to pharynx for removal

9. NOSE Structure Functions-What are the Functions?
Nasal septum separates interior of nose into two cavities
Mucous membrane lines nose
Frontal, maxillary, sphenoidal, and ethmoidal sinuses drain into nose (Figure 14-3)
Functions-What are the Functions?
Warms and moistens inhaled air
Contains sense organs of smell

10. Answer-Nose Functions
Warms and moistens inhaled air
Contains sense organs of smell

12. PHARYNX Structure (Figure 14-4)
Pharynx (throat) about 12.5 cm (5 inches) long
Divided into nasopharynx, oropharynx, and laryngopharynx
Two nasal cavities, mouth, esophagus, larynx, and auditory tubes all have openings into pharynx
Pharyngeal tonsils and openings of auditory tubes open into nasopharynx; tonsils found in oropharynx
Mucous membrane lines pharynx
Functions-What is the function of the Pharynx?

13. Answer-PHARYNX Functions Passageway for food and liquids
Air distribution; passageway for air

15. LARYNX Structure (Figure 14-5) Functions-What is the function?
Several pieces of cartilage form framework
Thyroid cartilage (Adam’s apple) is largest
Epiglottis partially covers opening into larynx
Mucous lining
Vocal cords stretch across interior of larynx
Functions-What is the function?

16. Function--LARYNX Functions
Air distribution; passageway for air to move to and from lungs
Voice production

19. TRACHEA Structure (Figure 14-6) Function—What is the function?
Tube about 11 cm (4.5 inches) long that extends from larynx into the thoracic cavity
Mucous lining
C-shaped rings of cartilage hold trachea open
Function—What is the function?
Obstruction
Blockage of trachea occludes the airway, and if blockage is complete, causes death in minutes
Tracheal obstruction causes more than 4000 deaths annually in the United States

20. Answer--TRACHEA
Function—passageway for air to move to and from lungs

22. BRONCHI, BRONCHIOLES, AND ALVEOLI
Structure
Trachea branches into right and left bronchi
Each bronchus branches into smaller and smaller tubes eventually leading to bronchioles
Bronchioles end in clusters of microscopic alveolar sacs, the walls of which are made up of alveoli (Figure 14-7)
Function-What is the function?

23. BRONCHI, BRONCHIOLES, AND ALVEOLI
Function
Bronchi and bronchioles—air distribution; passageway for air to move to and from alveoli
Alveoli—exchange of gases between air and blood (Figure 14-8)

25. LUNGS AND PLEURA Structure (Figure 14-9)
Size—large enough to fill the chest cavity, except for middle space occupied by heart and large blood vessels
Apex—narrow upper part of each lung, under collarbone
Base—broad lower part of each lung; rests on diaphragm
Pleura—moist, smooth, slippery membrane that lines chest cavity and covers outer surface of lungs; reduces friction between the lungs and chest wall during breathing (Figure 14-10)
Function—breathing (pulmonary ventilation)

27. RESPIRATION Mechanics of breathing (Figure 14-11)
Pulmonary ventilation includes two phases called:
Changes in size and shape of thorax causes what?
Air pressure differences actually cause air to move into and out of the lungs

28. Answer--RESPIRATION Mechanics of breathing (Figure 14-11)
Pulmonary ventilation includes two phases called inspiration (movement of air into lungs) and expiration (movement of air out of lungs)
Changes in size and shape of thorax cause changes in air pressure within that cavity and in the lungs

30. RESPIRATION Inspiration Active process—Define?
Inspiratory muscles include: _______and _____________.

31. Answer-RESPIRATION Inspiration Active process—air moves into lungs
Inspiratory muscles include diaphragm and external intercostals
Diaphragm flattens during inspiration—increases top-to-bottom length of thorax
External intercostals contraction elevates the ribs— increases the size of the thorax from the front to the back and from side to side
Increase in the size of the chest cavity reduces pressure within it; air then enters the lungs

32. RESPIRATION Expiration
Quiet expiration is ordinarily a passive process
During expiration, thorax returns to its resting size and shape
Elastic recoil of lung tissues aids in expiration
Expiratory muscles used in forceful expiration are: ____________ and _____________

33. Answer-RESPIRATION Expiration
Quiet expiration is ordinarily a passive process
During expiration, thorax returns to its resting size and shape
Elastic recoil of lung tissues aids in expiration
Expiratory muscles used in forceful expiration are internal intercostals and abdominal muscles
Internal intercostals—contraction depresses the rib cage and decreases the size of the thorax from the front to back
Contraction of abdominal muscles elevates the diaphragm, thus decreasing size of the thoracic cavity from the top to bottom
Reduction in the size of the thoracic cavity increases its pressure and air leaves the lungs

34. RESPIRATION Exchange of gases in lungs (Figure 14-12)
Carbaminohemoglobin breaks down into carbon dioxide and hemoglobin
Carbon dioxide moves out of lung capillary blood into alveolar air and out of body in expired air
Oxygen moves from alveoli into lung capillaries
Hemoglobin combines with oxygen, producing oxyhemoglobin
Exchange of gases in tissues
Oxyhemoglobin breaks down into: __________and ________.

35. RESPIRATION Exchange of gases in lungs (Figure 14-12)
Carbaminohemoglobin breaks down into carbon dioxide and hemoglobin
Carbon dioxide moves out of lung capillary blood into alveolar air and out of body in expired air
Oxygen moves from alveoli into lung capillaries
Hemoglobin combines with oxygen, producing oxyhemoglobin
Exchange of gases in tissues
Oxyhemoglobin breaks down into oxygen and hemoglobin
Oxygen moves out of tissue capillary blood into tissue cells
Carbon dioxide moves from tissue cells into tissue capillary blood
Hemoglobin combines with carbon dioxide, forming carbaminohemoglobin

36. BLOOD TRANSPORTATION OF GASES
Transport of oxygen
Transport of carbon dioxide
Volumes of air exchanged in pulmonary ventilation (Figure 14-13)
Volumes of air exchanged in breathing can be measured with a spirometer
Tidal volume (TV)—amount normally breathed in or out with each breath
Vital capacity (VC)—greatest amount of air that one can breathe out in one expiration
Expiratory reserve volume (ERV)—amount of air that can be forcibly exhaled after expiring the tidal volume
Inspiratory reserve volume (IRV)—amount of air that can be forcibly inhaled after a normal inspiration
Residual volume (RV)—air that remains in the lungs after the most forceful expiration
Rate—usually about 12 to 18 breaths a minute; much faster during exercise

38. REGULATION OF RESPIRATION (Figure 14-14)
Regulation of respiration permits the body to adjust to varying demands for oxygen supply and carbon dioxide removal
Most important central regulatory centers in medulla are called respiratory control centers (inspiratory and expiratory centers)
Under resting conditions, nervous activity in the respiratory control centers produces a normal rate and depth of respirations (12 to 18 per minute)
Respiratory control centers in the medulla are influenced by “inputs” from receptors located in other body areas:
Cerebral cortex—voluntary (but limited) control of respiratory activity
Receptors that influence respiration
Chemoreceptors respond to changes in carbon dioxide, oxygen, and blood acid levels—located in carotid and aortic bodies
Pulmonary stretch receptors—respond to the stretch in lungs, thus protecting respiratory organs from overinflation

40. TYPES OF BREATHING Eupnea— Hyperventilation— Hypoventilation— Dyspnea—
Apnea—
Respiratory arrest—

41. TYPES OF BREATHING Describe the following:
Eupnea—normal breathing
Hyperventilation—rapid and deep respirations
Hypoventilation—slow and shallow respirations
Dyspnea—labored or difficult respirations
Apnea—stopped respiration
Respiratory arrest—failure to resume breathing after a period of apnea

42. Question and answers
1. The upper respiratory tract includes all of the following except the:
a. nose
b. trachea
c. pharynx
d. larynx

43. ANS: B-Trachea

44. The mucous blanket:
a. only covers the nose and throat
b. traps dust, pollen, and other contaminants
c.only covers the alveoli and bronchioles
d. both B and C above

45. ANS: B
traps dust, pollen, and other contaminants

46. All of the following are paranasal sinuses except the:
a. frontal sinus
b. maxillary sinus
c. sphenoid sinus
d. mandibular sinus

47. ANS: D
mandibular sinus

48. The function of the epiglottis is to:
a. anchor the vocal cords
b. change the pitch of the voice
c. keep food from entering the trachea
d. both A and B above 

49. ANS: C
keep food from entering the trachea

50. The smallest of the air distribution tubes in the respiratory tract are the:
a. secondary bronchi
b. bronchioles
c. alveolar ducts
d. tracheae

51. ANS: C
alveolar ducts

52. Dyspnea is labored breathing that is often associated with:
a. hypoventilation
b. hyperventilation
c. eupnea
d. apnea 

53. ANS: A
hypoventilation

54. Which term refers to a normal respiratory rate?
a. dyspnea
b. apnea
c. eupnea
d. hyperventilation

55. ANS: C
eupnea

56. True/Fals
The organs of the respiratory system are designed to perform two basic functions: air distribution and gas exchange.

57. True

58. The respiratory membrane lines most of the air distribution tubes in the respiratory system.

59. False

60. The nicotine in cigarette smoke stimulates the cilia to beat rapidly in both directions, stopping the efficient removal of the trapped debris.

61. False

62. The four paranasal sinuses are named for the bones in which they are found. They are the frontal, parietal, sphenoidal, and ethmoidal.

63. ANS: F

64. The tonsils are located in the pharynx.

65. True

66. In some lung diseases, the lungs lose their elasticity and their ability to recoil. This would have the greatest impact expiration.

67. True

68. In order for external respiration to take place, the alveoli must have a higher oxygen concentration and a lower carbon dioxide concentration than the blood in the lung capillaries.

69. True

70. The cerebral cortex is responsible for the voluntary increase or decrease in breathing rate.

71. True

72. Any Questions