The lungs are part of the respiratory system, although their weight is small, but they fill a large part of the chest cavity. When extended, the surface of the lungs corresponds to the size of a tennis court – approximately 100 square meters.
The lungs are a spongy, paired organ made up of lobes. The two lungs are not the same size because part of the chest is occupied by the heart, so the left lung is smaller. The lungs provide our bodies with oxygen. They do not have their own muscles, their movement is initiated by the functioning of the chest and the diaphragm.
When inhaling, air passes through the mouth or the nasal cavity, through the nasopharynx, oropharynx, and larynx.
It continues its way through the trachea, then through the bronchi (meanwhile the inhaled air is cleansed, heated up and its humidity is increased), and then through the bronchial system, then reaches the alveoli where the gas exchange is taking place.