alcohol, effects

In biology, the effects of alcohol on cells. Alcohol differs from many other organic chemicals by affecting the way nerve cells operate when present in the body. At high concentrations it is poisonous and can kill all forms of life, including micro-organisms. In fact, alcohol can be used to preserve the remains of animals and plants for ever by preventing the micro-organisms of decay from breaking down the tissues.

Nerve cells in the brain are affected by the alcohol (ethanol) in alcoholic beverages. The result is that it reduces anxiety and makes people drowsy (sedative or depressant). It increases the effects of antihistamines and barbiturates and people can die as a result of taking these drugs with alcohol. However, in low doses the depressing effect is most marked on parts of the brain concerned with inhibiting extreme behaviour and making fine judgements. So people affected by alcohol are often uninhibited and unaware that they are not able to drive as safely as they should – in fact, one of the effects of alcohol is to give a sense of overconfidence in driving ability. Tests show that reaction time can be slowed by 10–30% because the brain is working inefficiently and messages to the muscles are delayed. Night vision may also be reduced by up to 25%. This makes alcohol quite dangerous.