Introduction to Chronic Obstructive Pulmonary Disease (COPD)

The lungs are a vital part of the respiratory system that enable oxygen from the air to be taken into the body (inhalation) while also enabling the body to eliminate carbon dioxide, a waste gas produced by the cells, through the air that is breathed out (exhalation). The respiratory system consists of the nose, throat, larynx (voice box), trachea (windpipe), and the lungs. The lungs consist of segments called lobes. The right lung has three lobes while the left lung, which is smaller, has only two lobes.

Respiration is the technical term used to describe the exchange of oxygen from the air that is inhaled into the body for carbon dioxide that is eliminated from the body by the process of exhalation. In the average person, the process of respiration occurs automatically at a rate of about 25,000 times each day.

When air is inhaled through the nostrils, the trachea (windpipe) brings the air down into the lungs. The upper portion of the trachea is located in the neck while the bottom portion extends down into the chest cavity where it divides into two tubes called the right and left bronchi. The right bronchus brings air into the right lung and the left bronchus brings air into the left lung. Within the lungs, the bronchi divide into smaller branches called bronchioles. At the end of the bronchioles are tiny air sacs called alveoli where the process of respiration, the exchange of oxygen and carbon dioxide, takes place in the lungs.