Drunk? Barely... wish I was. Ya see, you can be intoxicated but not drunk (which is inebriated).. some day you may understand that.
As for biology, yup, I dun took it too. I dun undeestand.
The liver converts alchohol into a form the brain can use (as with all drugs). It's always toxic, otherwise it wouldn't get ya all fugged up. Drugs are just that, chemicals that are toxic to the brain... that's why overdosing on alchohol will kill ya, cuz it makes your blood so toxic that your brain can't handle it and shuts down.
-SW