Teen brains are still developing
Heroin kills cells and affects your brain more directly.
brain
Alcohol by far as it does damage to your body and causes addiction.
I would say alcohol because it kills your liver and other important organs.
Lungs
The brain contains more blood
no not all alcohol goes to the brain more so the liver.
Adult mind become more matured then before overall its good for adult mind
The brain is mostly muscle muscle weighs more than fat,
no it really does it:>
Brain stem which controls breathing and heart rate. The lower the parts in the brain the more basic the functions the higher in the brain the more complex and evolved the function.
Neither, That alcohol (or drugs) kills brain cells is an urban myth.