Respiratory Flashcards
Structures across which gas exchange occurs
Thin-walled with large lumen
Provide intimate contact between inhaled air and blood in pulmonary capillaries that wrap the alveolar walls
Alveoli
Most common cell type
Connected to a thin basement membrane with a pulmonary endothelial cell on the other side (“respiratory membrane”)
Type 1 Alveolar Cell
Cuboidal cells; make and secrete surfactant
Type 2 Alveolar Cell
Reduces surface tension between water molecules lining inner alveoli surfaces
Surfactant
Alveolar macrophages; resident alveolar immune cells
Scavenge microorganisms, other particles
Type 3 Alveolar Cell
Deoxygenated blood flow
- Pulmonary trunk
- Pulmonary arteries
- Lobar arteries
- Capillary beds surrounding alveoli
Oxygenated blood flow
- Venules
- Small veins
- Pulmonary veins
If the number of gas particles in a given volume ___, pressure ____.
*Boyle’s Law
increases
increases
If temperature ___ while all other factors remain the same, pressure ____
increases
increases
If the volume ____ while all other factors remain the same, pressure ____.
increases
decreases
Respiratory system trying to clear irritants from the airways
Coughing and sneezing
Results from deepest possible breath
Yawn
Spasm of the diaphragm that causes rapid bursts of air through the vocal cords
Hiccup
When emotional states drive the ventilatory pattern
Laughing/crying
Attempt to exhale against a closed airway
Valsalva maneuver
Occurs between air in the alveoli and blood in the capillaries
External respiration
The rate of gas diffusion depends on the ____ ____ of the gas.
solubility coefficient
Transports more than 98% of blood’s O2
Hemoglobin
Contains 250-300 million hemoglobin molecules
Can carry up to 1.2 billion oxygen molecules
RBC
CO2 more readily binds to unoxygenated hemoglobin.
The Haldane effect
Removes the end products so the reaction can continue
Chloride shift
Chemoreceptors that detect chemicals in blood (e.g., PaCO2, PaO2)
Sensors
Respiratory center in brainstem (neurons in medulla oblongata and pons)
Integrators
Diaphragm and intercostal muscles that control breathing
Effectors
