When subjects had their brain scanned during pot use, it was shown to slow down brain activity.
When a normal person starts taking on a complex task, brain activity picks up, like solving a math problem, translating something from one language to another or drawing a picture.
So basically, you become dumber while high. Kids laugh at dumb things like why did the chicken cross the road jokes. When you are high, you may find legitimately dumb things funny than they really are.
Really? Didn't do that to me...I mean, you can say all of this about alcohol too....
Well, it does pollute your lungs just like tobacco smoke.
If you are still growing, then marijuana use will have a detrimental effect on your brain growth. This is why people who used pot before their brains fully developed have difficulty processing complex things, absorbing information quickly that they need to memorize.
I used since 14 (over a decade), haven't gotten any dumber; mostly when high, my brain would just be preoccupied on other things (basically, I wasn't thinking about memorizing/studying/doing important things when high; in fact, some people do it better high..); Again, you can say the same about alcohol (which is proven to be waaaaay worse)...
Marijiuana is a controlled substance because of THC content.
You can get some dandelion leaves, dry them, and then smoke it. Dandelion and marijuana are both weeds. But dandelion doesn't have THC so you won't get high.
Yes.

Wait, aren't you a cop/former cop?