RESP 103&105 COPD and Pleurisy Flashcards
(48 cards)
What is the pressure of air at sea level?
760mmHg
Where does the trachea bifurcate?
At the carina about TIV/V
What cells line the respiratory tract?
Ciliated columnar epithelial cells
What is contained within mucus to help fight infection?
anti-trypsins, lysozyme and immunoglobulin A
What cells line the wall of the alveoli and alveolar ducts?
Type 1 and 2 pneumocytes
Which cells in the alveoli secrete surfactant
Type 2 pneumocytes
What is the function of surfactant?
to decrease surface tension and prevent alveolar collapse
What is the tidal volume of lungs?
The volume of air drawn into and out of the lungs during normal breathing
What is the vital capacity of lungs?
The maximum tidal volume - breathing in and out as much as possible
What is the difference between resting and maximum expiratory/inspiratory volume?
expiratory reserve volume
inspiratory reserve volume
What is the volume of the lungs after a maximum inspiration called?
Total lung capacity
What is the volume in the lungs called after maximum expiration?
residual volume
What is the functional residual capacity?
The volume of air left in the lungs a the end of a normal breath
What is functional residual capacity determined by?
Outward elastic recoil of the chest wall and inward elastic recoil of the lungs
What is the normal intrapleural pressure?
-0.2 to -0.5 kPA
What happens to the intrapleural pressure during inspiration?
It becomes more negative = lung and alveolar expansion
What happens to the intrapleural pressure during expiration?
It rises but remains negative
What is Laplace’s law and why is it relevant in the lungs?
Describes how the pressure in a bubble is proportional to the surface tension and radius
In alveoli, producing surfactant reduces the surface tension as otherwise the high pressure inside the alveoli would suck fluid in and cause collapse
What is Darcy’s Law and what does it describe?
Describes flow through airways
alveolar pressure - mouth pressure / resistance to airflow
What does Pouseilles law describe?
That resistance is determined by radius and whether flow is laminar or turbulent
What is Daltons Law?
Total pressure = the sum of partial pressures of constituents
What is Ficks Law?
The rate of diffusion across a membrane is proportional to: concentration difference, membrane SA, diffusion constant and inversely proportional to thickness
What are the 4 stages in transport of oxygen to tissues?
Ventilation of alveoli by convection
Diffusion of 02 across alveolar membrane
Oxygenated blood is pumped around by convection
02 diffuses from capilliaries to tissues
Where are chemoreceptors found that control breathing?
medulla, carotic and aortic bodies
