Final answer:
Chronic bronchitis directly affects the airways, causing inflammation and narrowing of the bronchi due to swelling and mucus. It is a component of COPD which may also lead to damage in the alveoli, particularly in emphysema. However, in chronic bronchitis alone, it is the airways that are inflamed.
Step-by-step explanation:
In chronic bronchitis, the airways are primarily affected. This condition is characterized by the inflammation of the bronchi—air passages that conduct air into the lungs. The inflamed bronchi become narrow due to the swelling and excess mucus production, obstructing the airflow and leading to difficulty in breathing. While chronic bronchitis is related to chronic obstructive pulmonary disease (COPD), where the alveoli can also be damaged, in bronchitis itself, it is the airways rather than the alveoli that are directly inflamed. However, chronic bronchitis can contribute to the development of emphysema, a type of COPD where the alveoli are affected, by causing a breakdown of connective tissues reducing the number and elasticity of alveoli. It is important to distinguish between chronic bronchitis and other respiratory conditions like pneumonia, which primarily affects the alveoli.