Chapter 23
THE RESPIRATORY SYSTEM
Outline and Objectives
IINTRODUCTION
1. Discuss the cooperative effect of the respiratory and cardiovascular systems to
maintain homeostasis.
2. Define respiration and the three basic processes of respiration.
RESPIRATORY SYSTEM ANATOMY
3. Identify the structures of the respiratory system and indicate whether they are
a part of the upper or lower respiratory regions.
Nose
4. Describe the structure and function of the internal and external nose.
5. Discuss rhinoplasty.
Pharynx
6. Describe the distinct structures and epithelium found in the three regions of
the pharynx and relate these structures and epithelia to their purpose in
ventilation and swallowing.
Larynx
7. Discuss the arrangement of cartilage that supports the laryngeal soft tissue
components.
Voice Production
8. Describe the operation of the vocal tissues within the larynx in sound
production.
9. Discuss how the pitch of the sound can be changed, and explain what happens
when whispering occurs.
Trachea
10. Describe how the connective and epithelial tissue structures of the trachea
maintain an open airway and help keep the lungs clear of small particles.
11. Discuss tracheostomy and intubation and why such procedures might be
performed.
Bronchi
12. Describe the changes in the cartilaginous support, smooth muscle, and
epithelium as the bronchi progressively branch into smaller regions and how
their duties are modified.
Lungs
13. Discuss how the lungs are generally positioned and related to the serosal
membrane of the pleural cavity.
14. Describe the gross features of the lung structure and the connections to the
other organ systems.
Lobes, Fissures, and Lobules
15. Discuss the relative positions of the lobes of the lungs as divided by fissures,
and explain why there are an unequal number of lobes on each side.
16. Describe the physical relation of the lobules to the bronchioles, vessels, and
alveolar components.
Alveoli
17. Discuss how the different types of cells that populate the alveoli work
together, and explain the structure of the alveolar-capillary membrane and its
function in the diffusion of respiratory gases.
Blood Supply to the Lungs
18. Describe the route and alternative duties of the two vascular systems that
permeate lung tissue.
PULMONARY VENTILATION
19. Define pulmonary ventilation in terms of the physical properties that promote
the movement of air.
Inspiration
20. Discuss how Boyle’s law works through the action of the diaphragm and
external intercostal muscles in the production of pressure gradients that move
air into the lungs.
21. Discuss the properties of the intrapleural space that hold the lung tissue
against the chest wall during lung volume changes.
Expiration
22. Describe the characteristics of the lung tissues that assist the internal
intercostal muscles in contraction of the lungs during expiration.
Alveolar Surface Tension
23. Discuss how surface tension develops in alveolar fluid and how surfactant
limits the tension and collapse during expiration, as well as eases expansion of
the alveoli during inspiration.
24. Discuss what happens if an injury of the chest wall allows air to enter the
intrapleural space.
Compliance
25. Define compliance and the lung tissues that control it, and list some
conditions that compromise compliance.
Airway Resistance
26. List the factors that control airway diameter and consequent resistance and the
effect of air flow rate and required pressure gradients.
Breathing Patterns and Modified Respiratory Movements
27. Discuss the various terms used for different breathing frequencies and muscle
groups employed in distinct respiratory movements.
28. List the known functions and causes for modified respiratory movements.
LUNG VOLUMES AND CAPACITIES
29. Define the various lung volumes and capacities.
EXCHANGE OF OXYGEN AND CARBON DIOXIDE
30. Describe the cell and fluid compartments through which oxygen and carbon
dioxide must diffuse to get from alveolar air to the tissue cells and out of the
body.
Gas Laws: Dalton’s and Henry’s Laws
31. Define Dalton’s law in terms of the partial pressure of a gas and the units of
pressure, and then demonstrate how to calculate the number of mm Hg
produced by a gas with a set partial pressure in a container with a set total
pressure.
32. State and explain the partial pressures of oxygen and carbon dioxide in the air
and at pertinent points of the body.
33. Define Henry’s law and its relationship to the solubility of the respiratory
gases in the blood.
34. Discuss how the external pressure of a gas affects the physical state of that gas
dissolved in a fluid.
35. Discuss how Henry’s law can be used to increase the amount of oxygen in a
person’s blood.
External Respiration
36. Explain the diffusion of the respiratory gases between the lung alveoli and
lung capillaries.
37. Discuss the factors that affect the rate of external respiration.
Internal Respiration
38. Explain the diffusion of the respiratory gases between the tissue capillaries
and the tissues.
TRANSPORT OF OXYGEN AND CARBON DIOXIDE IN THE BLOOD
39. Discuss the role of the blood in transporting oxygen and carbon dioxide
between the lungs and tissues.
Oxygen Transport
40. Discuss the methods for transporting oxygen in blood.
Hemoglobin and Oxygen Partial Pressure
41. Discuss the effect of oxygen partial pressure on oxygen binding to and
dissociating from hemoglobin.
Other Factors Affecting Hemoglobin Affinity for Oxygen
42. Discuss factors other than the partial pressure of oxygen that influence the
affinity with which hemoglobin binds oxygen.
Comparison of Adult and Fetal Hemoglobin
43. Explain why it is necessary for fetal hemoglobin to have a greater affinity for
oxygen than maternal hemoglobin.
44. Discuss what occurs with carbon monoxide poisoning.
Hypoxia
45. Give the definition, causes, and effects of hypoxia.
Carbon Dioxide Transport
46. Describe the three main forms by which carbon dioxide is transported in
blood.
47. Explain how these forms change in the lungs versus the tissues.
Summary of Gas Exchange and Transport in Lungs and Tissues
48. Discuss how all the factors that influence oxygen and carbon dioxide content
in the blood interact to facilitate delivery of the gases to their respective
destinations.
REGULATION OF RESPIRATION
49. Cite the location of the neural centers that allow the respiratory system to
provide the disparate amounts of oxygen needed under the extreme range of
metabolic demands.
Respiratory Center
50. Identify the three brain stem centers that regulate respiration.
Medullary Rhythmicity Center
51. Discuss the mechanism by which the medullary rhythmicity center establishes
the basic cycle of ventilation.
Pneumotaxic Area
52. Discuss the interactions between the pneumotaxic area and the rhythmicity
center to initiate expiration and set the rate of breathing.
Apneustic Area
53. Describe how the apneustic area interacts with the rhythmicity center to
control the transition from inspiration to expiration.
Regulation of the Respiratory Center
54. Explain the influences from higher CNS areas and peripheral receptors on
ventilation patterns.
Cortical Influences
55. Discuss the means that limit conscious control over respiration.
Chemical Regulation
56. Discuss the negative feedback control system through which differing
chemical conditions in the blood regulate the breathing pattern.
57. Give the definition, causes, and effects of hypoxia.
Neural Changes Due to Movement
58. State how muscle movements stimulate appropriate changes in breathing in
preparation for exercise.
Inflation Reflex
59. Cite the components involved in the inflation reflex and their purpose.
Other Influences
60. List the other significant factors that influence breathing patterns.
EXERCISE AND THE RESPIRATORY SYSTEM
61. Describe the effects of exercise on the respiratory system.
62. Discuss why smokers have lowered respiratory efficiency.
DEVELOPMENTAL ANATOMY OF THE RESPIRATORY SYSTEM
63. Describe the development of the respiratory system.
AGING AND THE RESPIRATORY SYSTEM
64. Describe the effects of aging on the respiratory system.
DISORDERS: HOMEOSTATIC IMBALANCES
65. Discuss asthma, chronic obstructive pulmonary disease, lung cancer,
pneumonia, tuberculosis, coryza and influenza, pulmonary edema, and cystic
fibrosis.
MEDICAL TERMINOLOGY
66. Define medical terminology associated with the respiratory system.