Respiratory System Flashcards
Where does gas exchange take place?
Alveoli
How thick is the alveolar cell wall?
1 cell thick
The gas exchange process at the alveoli
Oxygen from air enters lungs diffuses across the membrane into the alveolar capillaries. The blood already there just returned from systemic circulation and is oxygen-poor, but CO2 rich.
What is the oxygen carrier of the circulatory system?
Hemoglobin
The membranes surrounding the lungs
Parietal pleura
Pulmonary pleura
To breathe in….
we increase volume, we decrease pressure
To breathe out….
we decrease volume, we increase pressure
Order of organs involved
Nares, pharynx, larynx, trachea
The larynx
vibrates as air passes and allows us to produce sounds such as talking, singing, and crying. This is not a passive phenomenon
Role of surfactant
- Premature infants are at risk for lungs collapsing because of insufficient surfactant production
- surfactant prevents alveoli from collapsing on themselves because their 1 cell delicate membrane
- it is a chemical species that reduces the surface tension of liquids
Order of inhalation
- Diaphragm muscles contract
- thoracic cavity expands
- pressure in pleural cavity becomes more negative
- lungs expand
Tidal volume
normal breath
Inspiratory reserve volume
any additional air that can be inhaled
Expiratory reserve volume
any additional air that can be exhaled
Total lung capacity
when we take the deepest breath possible. total volume
