Ch. 1 West Flashcards
How do oxygen and CO2 move between air and blood?
Simple diffusion i.e. from an area of high to low partial pressure
Fick’s law of diffusion states that the amount of gas that moves across a sheet of tissue is ______ proportional to the area of the sheet but ________ proportional to its thickness.
Directly proportional
Inversely proportional
What type of epithelium lines the proximal airways?
Ciliated columnar epithelium
As the large airways split and taper into smaller airways, cartilage tissue becomes replaced with _____
Smooth muscle
The larger airways contain no alveoli, and therefore constitute ____ _____ space
Anatomic dead space
Anatomic dead space is defined as:
Areas of lung that receive ventilation but no blood flow - volume is about 150 mL
When inspiration occurs, the diaphragm ______, which causes it to descend.
Contracts
What is the volume of the alveolar region?
2.5-3 L
In the conducting zone (trachea down to terminal bronchioles) the air/gas moves primarily via ____
Bulk flow
Once in the transitional and respiratory zones (respiratory bronchioles down to the alveolar sacs) air/gas moves via _____
Diffusion
The blood-gas interface is extremely thin (0.2-0.3 micrometers) and has an enormous surface area of about __ to ___ m^2.
50-100 m^2
Surfactant dramatically (raises/lowers) the surface tension of the alveoli
Lowers the surface tension- helps prevent alveolar collapse
Mucus is secreted by the ____ cells and ____ cells in the larger airways and cilia then moves debris up to the epiglottis, where it can be swallowed.
Goblet cells and mucus cells
Since alveoli have no cilia, debris are removed by ______ which then transport debris into the lymphatics for removal.
Macrophages
