Final exam Flashcards
Relationship between flow, Pressure, and Resistance for the movement of air in lungs
Flow=change in pressure/resistance
What keeps lungs inflated and prevents collapse?
Fluid layer between visceral pleura attached to the lung and parietal pleura attached to the chest wall
When diaphragm contracts and thoracic volume increases, what happens to pressure in the lungs?
Decreases
Decreased pressure in lungs and increased thoracic volume causes air flow in which direction?
Inside the lungs; high pressure to low pressure
Decreased pressure in lungs and increased thoracic volume causes _______ interpleural pressure.
Decreased
What scenario can cause a decrease in diffusion of gas molecules in blood?
Increased travel length
Oxygen is ____soluble in plasma then carbon dioxide.
Less
Gas exchange is driven by…
Simple diffusion, driven by partial pressure of gasses
PO2 is ____ Carbon dioxide in venous blood.
Less than
PCO2 is ____ oxygen in arterial blood.
Less than
Why does the body use hemoglobin to transport oxygen and not plasma?
O2 is not very soluble in plasma
Not enough O2 diffuses into blood plasma to carry out bodily functions
When breath holding, why is there an increase of PCO2 in the lungs?
CO2 constantly produced and leaving tissue(muscle)
Where does Oxygen bind to in hemoglobin?
Heme group
Carbon dioxide _____ transport through hemoglobin.
Can
How is carbon dioxide transported via bicarbonate ion?
CO2 in RBC react with H+ and HCO3- that enters plasma and carried to lungs. RXN catalyzed by carbonic anhydrase
What replaces the bicarbonate ion in RBC, is it replaceable?
Chloride, yes
Carbon dioxide is ____ majorly transported via plasma.
Not
What is special about the Hb saturation curve?
It’s sigmoidal with a safety plateau where almost complete saturation can be achieved at different PO2 during Hb loading
What is the affinity to oxygen during a RIGHT shift in the Hb saturation curve?
Reduced
What is the affinity to oxygen during a LEFT shift in the Hb saturation curve?
Increased
LEFT Hb shift =____ metabolic activity, ___pH, ___temperature
Decreased, increased, decreased
Increased metabolic activity= ____ CO2 production and ____ in H+ ions
Increase, Increase
During increased metabolic activity, what effect causes reduced oxygen affinity due to binding to excess H+?
Bohr effect
Where is the integrating center for monitoring PO2, PCO2, and pH levels in blood?
Brainstem
How is PO2 measured in arterial blood?
Peripheral chemoreceptors in aorta and carotid bodies
How is PCO2 monitored in the body?
The H+ concentrations in CSF via central chemoreceptors in brainstem
Central chemo receptors measure…
CO2 and brain pH
Increased CO2, _____ breathing
Increases
