A biology teacher wishing to demonstrate to his students the harmful effects of alcohol on living organisms showed them a beaker with pond water in which there was a thriving civilization of worms.
When he added some alcohol into the beaker the worms doubled-up and died.
“Now,” he asked,” what do we learn from this?”
An eager student gave his answer.
“Well it is obvious,” he said ” if you drink alcohol, you’ll never have worms.”