There are many parts of the respiratory system. The human respiratory system starts from the nose from where the air is inhaled, then, the air travels through the nose and then enters the trachea, which is the windpipe.
The trachea splits into two parts, one of which enters the right lung and the other enters the left lung. These tubes that the trachea split into are known as bronchi (a single tube is known as bronchus).
Main Function of Bronchi
Allowing Air to Pass
One of the primary function of bronchi is to allow air to pass through it. As the trachea splits into two parts, the inhaled air enters the bronchi. From here, it passes through its further divisions, which are known as bronchioles. This then divides to form alveolar ducts which eventually end into alveolar air sacs or alveoli.
Thus, these tubes basically act as a passage for air to pass from. It is a common misconception that they are responsible for the exchange of air in the body. It in no way aids in, or brings about exchange of air, as this is solely done by the alveolar air sacs.
The main etiology of asthma lies in the fact that the bronchi become restricted, that is, their lumen decreases. Due to this, there is insufficient air that reaches the lungs and so, the person starts wheezing. This is especially seen in chronic bronchial asthma.
The bronchi are lined by various types of cells. These include ciliated cells, and goblet or mucus cells. The ciliated cells are called so because they have cilia, which is a hair like projection that moves in a rhythmic fashion, at one end of the cell. The goblet cells are cells that are large and these secrete mucus.
When air enters from the nose, the nose hair and cilia try to prevent and trap pathogens that come in. However, the humidified air that enters the trachea, then passes from the bronchi. The cilia and mucus present here further prevent pathogens from entering any further into the lungs.
Their role is crucial, because if pathogens enter into the lungs, it could lead to various respiratory system diseases. This is especially seen when there is malfunctioning of cilia, as is seen in bronchitis, where there is inflammation of this respiratory part.
Irregularities in functioning of bronchioles can lead to many problems, which can be partly diagnosed by analyzing the bronchial breath sounds. To reach a final diagnosis though, one will have to opt for various tests and may even need to do a bronchoscopy procedure, wherein a camera is passed into the respiratory tract to check for problems or blockages.