Topic list 3 Flashcards
What is residual volume?
air remaining in the lungs after complete exhalation
What are the standard capacities?
inspiratory capacity, functional residual capacity, vital capacity, total lung capacity
What is functional residual capacity?
volume of air at the end of exhalation during normal breathing
What is vital capacity?
Total volume of exhaled air from max inspiration to max expiration
What is total lung capacity?
total volume of air in the lung at the end of max inspiration
What is the pressure at the base of the pleural cavity?
-2.5 cm H20
What is the pressure at the apex of the pleura cavity?
-10 cm H20
When are the lungs the smallest?
when transpulmonary pressure = 0
What is emphysema?
Loss of alveoli and of their elastic tissue
What type of system is the pulmonary circulation?
Low pressure / low resistance system
Where is the ventilation / perfusion ratio at its lowest?
at the bottom of the lung, where Q exceeds Va
What does Graham’s law state? (2)
rate of diffusion of a liquid is proportional to its solubility, and inversely proportional to the sqrt of its molecular weight
What is special about the gamma sub-unit of fetal Hb?
It does not bind to 2,3BPG and thus has increased affinity for O2
What is the O2 dissociation curve?
curve that illustrates the relationship bw pO2 in blood and number of O2 molecules bound to Hb
When is the Hgb saturation especially dependant on pO2?
under 60mmHg pO2
