What are the consequences of smoking?

Smoking have bad long term and short term effects on a person's health due to the harmful substances in cigarettes. Firstly, it can causes emphysema. This is when the alveoli's bubbly-like shape is reduced, decreasing the overall surface area of alveoli. This then decreases the diffusion rate of oxygen/carbon dioxide in and out of the bloodstream to the alveoli. As a result, less oxygen is delivered to muscles to carry out respiration. This makes people extremely tired and out of breath even with the movement of climbing up the stairs. Smoking also can increase the risk of cancer, as tar is a carcinogen which coats the tubes and alveoli. Smoking can also lead to bronchitis, which is inflammation of the bronchi caused by the irritation of smoke. Ciliated epithelial cells lining the tubes of the lungs are damaged meaning sticky mucus can not be effectively removed, trapping pathogens and further irritating the lungs including the bronchi. Carbon monoxide is a harmful substance that is inhaled when smoking, this replaces oxygen in haemoglobin preventing effective delivery of oxygen to the muscles.