Bronchiectasis is a chronic inflammatory or degenerative condition of one or more bronchi or bronchioles of the lungs marked by dilatation and loss of elasticity of the walls. (sciencedaily.com)
Bronchiolitis, a condition in which small breathing tubes in the lungs called bronchioles become infected and clogged with mucus, is the most common acute lower respiratory infection in children. (sciencedaily.com)
In the lung, the pulmonary alveoli are spherical outcroppings of the respiratory bronchioles and are the primary sites of gas exchange with the blood. (sciencedaily.com)