Drugs (wp)

A drug is a substance which alters the way the body works.
e.g. Caffeine, present in coffee and tea, is a stimulant.
Some drugs like medicines are beneficial.
In our body, chemical reactions are going on all the time to keep thebody working properly. Medicines are usually made up of manychemicals; the active ingredient is a drug which helps the body whenit is not working correctly.
e.g. antibiotics fight the micro-organisms (germs) which can cause
Some drugs can damage our health because of the way they affect ourbodies and our lifestyle. e.g. Nicotine, present in cigarette smoke, speeds up the heart rate
Alcohol gives a feeling of well-being but slows us down.
It damages the liver and brain if we drink too much.
LSD causes hallucinations e.g. users think they can safely fly
out of windows ten stories high!
Cannabis heightens the sense of colour, taste and music.
It makes most users relaxed and talkative.
Ecstasy gives a feeling of well-being and increased alertness.
Users push their bodies to the limit and heart failure can be
the result.
Some drugs are legal e.g. medicines, alcohol, Nicotine and Caffeine.
Others are illegal e.g. Cannabis, LSD and Ecstacy.
Some drugs are addictive: we are unable to manage without them.
Though we may know they are harmful, we cannot give them up. A common
example of an addictive drug is alcohol.
Alcohol is made by the reaction between Glucose and yeast, a reaction
known as fermentation.
Enzymes in the yeast speed up the conversion of Glucose into analcohol called Ethanol. Carbon dioxide gas is also produced.
We can make alcohol from Glucose in the laboratory: After a few hours bubbles of Carbon dioxide come out of themixture. After a few days the froth dies down and theliquid smells of alcohol.
The Glucose required to make alcohol is obtained from plants.
Alcoholic drinks are made by fermenting the actual plant materialcontaining the Glucose. Different plants give different flavours andtherefore different drinks e.g.
Fermentation produces very dilute alcohol (5-12%). Most of themixture is water! We can increase the concentration of the alcohol by a process calleddistillation: Alcohol boils at 78 0C; Water boils at 100 0C. When we heat the mixturethe alcohol boils out of the mixture first, condenses in the condenserand drips into the beaker as nearly 100% alcohol! Spirits (whisky, gin, vodka etc) are made from this more concentratedalcohol.
A bottle of alcopop or a pint of beer contain about 2 units ofalcohol.
A pub measure of spirit or a glass of wine contain about 1 unit ofalcohol.
Alcohol is broken down in the body at about 1 unit per hour.
The alcohol made by fermentation of Glucose is called Ethanol.
Ethanol is not the only alcohol.
Methanol is a very poisonous alcohol causing blindness and death!Methylated spirits (meths) contains Methanol. The purple dye is awarning. A bad-tasting substance is also added to prevent people fromdrinking it.

Source: http://www.iandalgleish.co.uk/notes/int1/drugs.pdf