The respiratory zone is the site of O2 and CO2 exchange with the blood.
The respiratory bronchioles and the alveolar ducts are responsible for 10% of the gas exchange. The alveoli are responsible for the other 90%.
The respiratory zone represents the 16th through the 23rd division of the respiratory tract.
Famous quotes containing the word zone:
“He who, from zone to zone,
Guides through the boundless sky thy certain flight,
In the long way that I must tread alone,
Will lead my steps aright.”
—William Cullen Bryant (1794–1878)