Occupational Safety and Health Administration. 1  Department of Labor, Labor Department, DoL, Labor - the federal department responsible for promoting the working conditions of wage earners in the United States; created in 1913.
The oxygen and carbon dioxide exchange take place in the alveoli. Primary bronchi are located on the upper portion of the lungs, secondary bronchi is located at the center of the lungs and tertiary bronchi is located near bottom of the organs above the bronchioles.
secondary bronchi (location, function). Location: extend from primary bronchi to tertiary bronchi within lungs; right lung has 3, left lung has 2 (corresponding to lobes of lung) Function: conduct air into and out of lobes of lung.