Biological Consequences of Smoking in Social Aspects Related to It

· DESCRIBE THE BIOLOGICAL CONSEQUENCES OF SMOKING IN SOCIAL ASPECTS RELATED TO IT.
A cigarette is a drug.You can become addicted to it.People who try to stop smoking may develop withdrawal symptoms if they have smoked heavily for a long time.These symptoms include a craving to smoke,becoming sleepless and irritable,numbness in the arms and legs,an inabilty to concentrate on their work and coughing more than usual.These unpleasent symptoms make some people continue to smoke,even though the symptoms usually disappear in a relatively short time.
Smoking causes a number of diseases,some of them life-threatening.Cigarette smoke contains over 4000 chemicals,some of which are harmful to the body.We shall find more about the ones that have been linked to health problems.
· NICOTINE
This is the addictive drug that is present in tobacco.
· It stimulates the brain at first making the smoker feel alert,and relaxes the muscles.Later,it dulls the brain and senses.
· It causes the release of adrenaline.This increases the rate of heartbeat and blood pressure.
· It makes blood clot easily.Therefore,it increases the risk of blood clots blocking blod vessels.If such clots block the coronary arteries,a heart attack may occur,or if they occur in capillaries of the brain,a stroke may result.

· CARBON MONOXIDE
· If the concentration of carbonmonoxide is the air is increased by 1%,it can produce a dealy effect-a person inhaling such a high concentration of the gas may die within ten minutes.This is because carbonmonoxide reduces the efficiency of the red blood cellsto transport oxygen.
· It increases the rate at which fatty substances are deposited on the inner walls of arteries,causing their lumens to become narrower.This can cause atherosclerosis.
· It damages the lining of blood vessels,thus increasing the tendency of the blood to clot and so block blood vessels.

· TAR
This is a brown,sticky substance that accumulates in the lungs during smoking.
· It contains many cancer-causing(carcinogenic) chemicals.Normally cell divison occurs continously in the lungs to replace the epithelium or membrane of the air sacs.Tar induces these cells to divide at an abnormal rate.Such uncontrolled multiplication of cells results in outgrowths or lumps of tissue(cancers).These block off the air sacs,reducing the efficiency for gaseous exchange.
· It paralyses the cilia lining the air passages.This prevents the cilia from removing dust particles from the lungs and trachea.

· IRRITANTS
Examples include hydrogen cyanide and acrolein.
· These substances paralyse the cilia in the air passages and weaken the walls of the alveoli.
· They irritate the cells lining the air passages causing them to produce mucus.This,in turn,causes a 'smokers' cough'. The coughing bursts the weakened walls of the alveoli,causing a decrease in wall area as many minute alveoli coalesce to form a reduced number of enlarged alveoli.This process eventually causes the gaseous exchange surface in the lungs to become greatly reduced.

EFFECT OF SMOKING ON THE LUNGS:
Smoking has a wide variety of health effects and can affect every organ of the body.But one of the organs that is most directly effected is the lungs. This may not be surprising as this is the organ in direct contact with cigarette smoke. The long-term effect of smoking on the lungs is quite well documented.Cancer of the lungs is largely due to smoking.It is estimated that 87% of cases of lung cancer in the US are smoking related.

One of the most common illnesses of the lungs related to smoking is chronic bronchitis which effects the bronchi within the lungs. Excessive mucus accumulates and obstructs the smaller structures known as the bronchioles,a great deal of difficulty in breathing occurs and this causes increase in pressure within the alveoli and if this becomes severe enough to rupture the alveolar membranes,then another more serious disease known as emphysema occurs. Emphysema is common among people who have been heavy smokers for a number of years,and this condition causes a reduction in the gaseous exchange of carbondioxide from the capillaries into the alveoli and of oxygen from the alveoli into the capillary blood.Increased resistence within the lungs can ultimately lead to right sided heart failure.
This cartoon represents what smoking does to lungs.

EFFECTS OF SMOKING IN SOCIETY:
Smokers are not only killing themselves but are also killing other people who are exposed to their cigarette's smoke. Passive smoking is when smoke is breathed in by someone other than the smoker. Passive smoking carries all the same health risks as smoking, and it’s particularly dangerous for children.
What effects can passive smoking have on non-smokers?
Short-term effects:
Being exposed to second-hand smoke is generally pretty unpleasant – it may give you a headache, cough or sore throat. It can also irritate your eyes and make you feel sick or dizzy. If you have asthma, being in a smoky place may make your symptoms worse. And of course, although the smell of smoke on your clothes and hair may be less serious healthwise, it’s often more irritating.
Long-term effects:
If you're regularly exposed to second-hand smoke, your risk of developing smoking-related diseases substantially increases. The World Health Organization (WHO) estimates that second-hand smoke increases your risk of heart disease and lung cancer by up to a third. Not only that, you’re more likely to develop chronic obstructive pulmonary disease, which causes problems with breathing.
Effects on children:
About two million children in the UK are exposed to tobacco smoke at home. However, the good news is that with the introduction of new smoking laws, and as people become more aware of the dangers of smoking, this number is slowly dropping.
Children who are exposed to second-hand smoke are at an increased risk of a number of serious conditions, including:
I. bronchitis and pneumonia
II. asthma
III. coughing and wheezing
IV. middle ear infections