1.a Review Of Pulmonary Anatomy And Physiology Flashcards
What are the five functions of the lungs?
The five functions of the lungs are as follows:
a. transferring oxygen from the atmosphere to the blood, and eliminating carbon dioxide
b. metabolizing, detoxifying, and excreting both endogenous (internal) and exogenous (external) substances
c. defending the lung against infection and pollution
d. providing immunological processes that occur independently from other parts of the body
e. synthesizing substances, such as surfactant, that line the respiratory units
What is the main difference between bronchi and bronchioles?
Bronchi contain cartilage. Bronchioles are non-cartilaginous or membranous.
How is airflow affected by the decreasing size of the airways between the bronchi to the bronchioles?
Because the total cross-sectional area of the lung actually increases between the large airways and the bronchioles, resistance to airflow decreases.
Under what conditions can spirometry help in the assessment of small airway disease?
The small airways (less than 2 mm in diameter) contribute only 15% to the total airway resistance. Therefore, considerable disease must be present before abnormal results show on spirometric testing.
What structures comprise the conducting airways?
The trachea, bronchi, and non-respiratory bronchioles make up the conducting airways.
What makes up the acinus?
Actual gas exchange occurs in the acinus: the respiratory bronchiole, alveolar duct, alveolar sac, and individual alveolus.
Describe two basic cell types in airway lining. What role do these cells play in pulmonary defence?
The airways are lined with ciliated epithelial cells and goblet cells. The mucous layer (produced by the goblet cells) on the ciliated cells forms the ciliary escalator. This is a primary defence mechanism for removing particulates. Note the detrimental effects on this mechanism produced by smoking.
How does smoking contribute to lung disease?
Smoking impairs the lungs’ natural defence mechanism by irritating the airways and impeding the function of the macrophages and the mucociliary escalators.
What does the term synergistic mean? What does this have to do with smoking and occupational exposures to airborne contaminants?
Synergistic means that the combined effect of two or more substances is greater than the effects of each added together.
Smokers who receive prolonged occupational exposures to other airborne contaminants may develop heart and lung disease and cancer more readily than non-smokers with comparable exposures. These diseases progress more rapidly in smokers because of the damage done to the lungs by smoking.
Name respiratory hazards classified by their impact on the respiratory tract.
Hazards classified by their impact on the respiratory tract include these:
• asphyxiants
• irritants
• fibrosis producers
• allergens
• carcinogens
