Still, the majority of teens do not smoke pot. Marijuana is a mind-altering drug, which can change the way a person thinks. The chemicals in marijuana block certain messages from being transmitted in the brain.
Marijuana tends to affect the parts of the brain that control memory, attention span and learning.
Marijuana is usually a brown, green or gray mixture of dried parts of the cannabis plant. THC builds up in the smokers' bodies, and it can take weeks for the body to rid itself of the chemicals from just one joint. Marijuana is also often put in foods as well, such as brownies and cookies. It can be very habit-forming. Irregular menstrual periods and ovulation in women, leading to possible infertility Diminished or lack of sex drive and enjoyment Increased risk of cancer.