Smoking addiction is harmful because it produces polycycllic aromatic hydrocarbons which cause :

Options

A. reduction in oxygen transport
B. increase in blood pressure
C. cancer
D. retardation of growth of foetus.

Answer

C

Explanation

Cancer is caused by cells dividing repeatedly out of control . They cease to respond to the normal signals around them and from unspecialised masses of cells called tumours . Lung cancer usually starts in the epithelium of the bronchioles, so - called bronchial carecinoma . It then usually spreads throughout the lungs . It is caused almost exclusively by smoking . Tobacco smoke contains chemicals responsible for lung cancer . The most important of these are polycyclic hydrocarbons which are converted in the body to carcinogens.
Besides , carbon monoxide combines with haemoglobin and reduces oxygen transport by about 15% in smokers and nicotine increase blood pressure , heart rate and constriction of blood vessels.