How it works

Here is a summary of how the respiratory system works.

Exchanging Gases

It is necessary to maintain a constant supply of oxygen and remove carbon dioxide. This happens through the exchange of these gases between the body and the environment. Externally, an exchange takes places through the nasal and oral cavities.

Internally, this exchange occurs between the lungs and the bloodstream. As a result, an important one of the respiratory system functions reaches completion.

Filtering the Air

It is essential to filter the air before it reaches the lungs. Any dust particles or possible toxins are removed as these can damage the lungs. This filtering process takes place in the nasal cavity as well as the trachea and the bronchia.

These components of the respiratory system have a lining of cilia which trap dust and other small particles.


Breathing requires inhaling and exhaling of air. So, oxygen enters the respiratory tract while carbon dioxide leaves it. This process takes place with the help of the diaphragm which is a muscle. When this muscle relaxes, it pushes the air out of the lungs.

On the other hand, when it contracts, it creates sufficient room for the lungs to expand and receive air.

Supplying and Removing Gases

The supply of oxygen and removal of carbon dioxide takes place between the lungs and the blood. So, it is one of the important respiratory system functions. Such a process occurs through blood capillaries. In fact, numerous blood capillaries are found in the alveoli which facilitate this process.