Major cause of respiratory problems is unhealthy air, containing smoke and other pollutants. Lung cancer is the one of the major diseases of respiratory system. Cancer or carcinoma is basically malignant tumor of potentially unlimited growth that expands locally by invasion and systemically by metastasis. Instead of lung tissues there are tumor for which cancer can occlude passages ways of respiratory. The major cause of lung cancer especially in young adults is SMOKING. Person that smokes or live in a smoky and congested areas has 10% ten percent more chance of develop lung cancer as compared to person who do not smoke. About 90% of lung cancer is caused by smoking. Recent research shows that there are more than 10 dangerous compound of tar of tobacco smoke are involved in causing cancer.
Tuberculosis is another disorder of respiratory system. In fact, it is caused by MYCOBACTERIUM TUBERCULOSIS bacteria. Pulmonary tuberculosis effect lung in a way that it resulting in cough and fever. Poor people are effected more commonly by this diseases. MYCOBACTERIUM grows due to malnutrition and poor living conditions. This diseases can be curable with proper medical attention. It is a contagious diseases.
One of serious respiratory diseases is asthma associated with severe paroxysm of difficulty in breathing. Asthma is the type of attack for more or less frequent intervals. If any allergic agent like pollen, spores, cold, humidity, pollution expose to patient then sudden reaction is shown by contraction of small bronchiole that result in difficulty in breathing due to the release of inflammatory chemicals such as histamines.
The break-down of alveoli of lung is called emphysema. It usually common in smokers because the substance that present in tobacco weaken the walls of alveoli. Due to the break-down of tissues, the lung are enable to trap the air and do not come back to it position as a result the effected person cannot oxygenate his blood properly and least exertion makes him breathless and exhausted.
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