The bronchial tubes are part of an internal structure known as the respiratory tree. This structure is part of the respiratory system, which allows humans to exchange the air in their lungs. People need to breathe in air that is rich in oxygen. The air they breathe out has poor levels of oxygen. These tubes connect the lungs to the trachea to facilitate this process.
The trachea, also known as the windpipe, allows air to flow into two hollow branches called the bronchi, or bronchial tubes. One tube is connected to the right lung. The other is connected to the left lung. These extend into many branches, known as bronchioles, which allow a large amount of air to be exchanged over the whole of each lung.
It may be easier to visualize the trachea as a huge root. That root extends down some distance and branches off into two large roots, which are the bronchial tubes. These two large roots veer off in different directions and become a network of small roots, or bronchioles, that cover a large area.
The bronchial tubes are located at about the center of a person’s chest. They connect to an upper portion of the lungs, known as the hilum. The bronchial tube that branches to the right is shorter than the one that goes to the left. This is due to the positioning of the heart, which is on the left side of the chest.
The inside of the bronchial tubes is lined with a mucous membrane. That membrane contains tiny structures that act as filters. If particles are breathed in with the air, these miniature filters catch them.
The bronchi are held open by semi-circle structures that run the length of them. These hold the passageway open, allowing the air to flow smoothly. When a person inhales, the bronchi extend in conjunction with the expansion of the lungs. When the person exhales the size of these parts is reduced to normal.
In some cases, inflammation or blockage cause an abnormal expansion of the bronchi. This condition is known as bronchiectasis. It can have an effect on parts of the body that are not directly related to the respiratory system.
In some other instances, the bronchial tubes become swollen or infected and cause a disorder known as bronchitis. This is common among smokers and people who are exposed to high levels of pollution. This condition is generally caused because the mucous filtering system becomes too dirty. It is usually characterized by a cough that produces a significant amount of phlegm.