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:
“The human race is a zone of living things that should be defined by tracing its confines.”
—Italo Calvino (1923–1985)