The Effects of Smoking. Describe the effects of smoking on the mammalian gas exchange system , with reference to the symptoms of chronic bronchitis emphysema (chronic obstructive pulmonary disease or COPD) lung cancer. C onstituents of cigarette smoke that cause damage to health.
Describe the effects of smoking on the mammalian gas exchange system, with reference to the symptoms of
Cigarette smoke contains over 4000 different chemicals. The main problems are caused by :
SEM of a lung cancer cell.
Cancer cells divide rapidly in a chaotic, uncontrolled manner.
They may clump to form tumours, which invade and destroy surrounding tissues.
Lung cancer is a common form of cancer, frequently associated with smoking tobacco. It often develops at the entrance to the bronchi
It causes a persistent cough, shortness of breath and chest pain. Blood may be coughed up in sputum.
Cancer may spread to other areas of the body.
Treatment includes surgical excision of the affected areas of the lung, with radiotherapy and chemotherapy.
Black deposits of tar in tissues
Large cancerous tumour
BronchitisInflammation of the airway lining, damaged cilia, increased mucous production. Persistent cough, mucus filled with microbes and white blood cells
SEM of human lung tissue affected by emphysema.
Emphysema is a disease in which the alveoli of the lung become enlarged and the walls separating them are damaged.
This damage occurs as a result of elastase enzyme breaking down the elastic fibres which allow the alveoli to expand and recoil. There is difficulty exhaling.
Surface area for gaseous exchange is reduced, restricting oxygen uptake. This may cause breathlessness, bluish skin, and heart or respiratory failure.
Occurrence of emphysema is strongly associated with smoking.
Treatment of emphysema is with drugs and the cessation of smoking.
Describe the effects of
nicotine and carbon monoxide
in tobacco smoke on the
with reference to the course of events leading to
Explain how Nicotine and
Carbon Monoxide contribute to the occurrence of
Coronary Heart Disease and Strokes