Respiratory System Flashcards
(64 cards)
What gaseous exchange occurs in the lungs?
O2 entering the blood, and CO2 leaves it
How does respiratory system regulate pH?
by adjusting CO2 levels in the blood
What is Phonation?
production of sounds and speech from air movement over vocal cords
What are the 3 conducting airways?
- Trachea
- Bronchi
- Nonrespiratory bronchioles
How many divisions occur in the airway before the respiratory unit of the airways arises?
16 divisions
What are the 2 respiratory units of the airways?
- Respiratory bronchioles
2. Alveolar Ducts
What are Alveoli?
thin-walled polyhedral sacs organized into alveolar sacs
Where does gas exchange occur in the lungs?
across alveolar walls of alveoli, which form the air-blood barrier
What is the name of the mutual central opening of alveolar sacs?
alveolar ducts
What are the 2 types of alveolar cells?
- Type I Alveolar cells
2. Type II Alveolar cells
What is the total surface area that Type I alveolar cells occupy in lungs?
92%
What is the weakness/problem of Type I alveolar cells?
very susceptible to chemical injury; ex: smoking and pollution
What intracellular structure does Type II alveolar cells contain? What do they do?
Lamellar bodies (storage of pulmonary surfactat)
What is the function of pulmonary surfactant?
Coat type I alveolar cells and prevent their collapse
What cells in the lungs are susceptible to SARS-CoV-2 infection?
Type II alveolar cells
What is the most abundant and 2nd most abundant phospholipid in pulmonary surfactant?
1st - (75%) phosphatidylcholine
2nd - (10%) - phosphatidylglycerol
Why are the 2 things expressed in Type II alveolar cells that make them susceptible to SARS-CoV-2 infection?
- ACE2
2. TMPRSS2
What 4 things are a part of the lung parenchyma?
- Alveoli
- interstitium
- bronchi
- bronchioles
Why is the lung parenchyma, particularly the alveoli highly elastic? (even without pulmonary surfactant)
stretches in response to mechanical stress AND exhibits high passive recoil when stress is removed.
What are the 2 ways that the volume of the thoracic cavity can be altered?
- LENGTH of the cavity
2. WIDTH or anteroposterior diameter of the cavity
What is tidal volume?
amount of air that is moved in and out of lungs during rest
What is inspiratory reserve volume?
if you were to continue to breath in after a normal inspiration from rest
What is vital capacity?
The total amount of air that can be moved from forceful inspiration and expiration
What is the average total lung capacity?
Sum of all volumes : ~6L