The Facts.

Since there is a very powerful active ingredient in marijuana, there is a 100% chance that it will affect the brain and activate the activity of certain brain cells. When marijuana is smoked, the effects are felt quicker compared to eating marijuana. When it is baked into food or brewed in tea, the effects take longer to get felt but last for much longer. Usually the effects are only felt for about 3 hours or so. There are things in your brain called Cannabinoid Receptors that affect pleasure, memory, thought, perception of time, and movement. These receptors are often altered and influenced when surrounded by marijuana. If heavy doses are administered they can cause hallucinations, impaired memory, or becoming delusional (Health). Usually the user experiences dry mouth and a dry throat. They can also experiece an increased heart rate and can often raise the heartbeats by 20-50 beats per minute (Marijuana). A lot of times people that smoke marijuana have trouble remembering things, have difficulty concentrating, paranoia, and red, bloodshot eyes. Headaches, nausea and minor changes in reproductive organs can also occur (Marijuana's Adverse Effects). Despite all of these effects that seem bad, smoking a couple joints doesn't come close to effects people experience due to smoking cigarettes. Cigarettes are more highly addictive and so is alcohol. Although cigarettes and alcohol are highly addictive, they are both legal and allowed after a certian age.

http://alcoholism.about.com/od/pot/a/effects.htm