Lungs are a pair of respiratory organs situated in a thoracic cavity. Lungs are mainly responsible for the exchange of oxygen and carbon dioxide between the air we breathe and the blood. Right and left lung are separated by the mediastinum. Texture of Lungs is soft and Spongy, its color in Young people is brown, in adults its mottled black due to deposition of carbon particles. Weight of Right lung is approx 600 grams and Left lung is 550 grams. Air enters the body via nose or mouth. The air enters the main windpipe, called the trachea, and continues en route to each lung via either the right or left bronchi.
The lungs are separated into sections called lobes, two on the left and three on the right. The air passages continue to divide into ever-smaller tubes, which finally connect with tiny air sacs called alveoli. This gradually branching array of tubes is referred to as the tracheobronchial Tree.
Lung Protection System
The lungs have several ways of protecting themselves from irritants:
- Our nose acts as a filter, preventing large particles of pollutants from entering the lungs.
- If an irritant does enter the lung, it will be stuck in a thin layer of mucus (also called sputum or phlegm) that lines the inside of the breathing tubes. Spitting up sputum is not “normal” and does not occur unless the individual has chronic bronchitis or there is an infection, such as a chest cold, pneumonia or an exacerbation of Chronic Obstructive Pulmonary Disease (COPD).
- Cough is another protective mechanism; cough is not a normal occurrence and is the result of irritation to the bronchial tubes. A cough can eject mucus from the lungs faster.
- Bands of muscle surround the airways in the lungs, when the lungs are irritated, these muscle bands can tighten, making the breathing tube narrower as the lungs try to keep the irritant out. The speedy tightening of these muscles is called Bronchospasm. Bronchospams may cause serious problems for people with COPD and Asthma, because narrowed airways make it difficult to breathe.
Large numbers of people suffer from these lung related diseases:
- COPD (chronic obstructive pulmonary disease)
- Lung cancer
- Pulmonary edema