A lot of the effects of smoking marijuana are short-term, which is why many people don't see it as a big deal. These include distorted perception, loss of memory and coordination, increased heart rate, and anxiety. The THC in marijuana can make you have hallucinations and disorientation. It also harms your immune system and makes you generally more susceptible to illness. Some long-term effects are in the lungs, which you might want to consider if you want to play basketball. You are more likely to get chest illnesses, lung infections, and blocked airways, as well as just coughing a lot. Your memory would probably also go back to normal if you quit. Also, I think smoking it can just lead you to a lot of bad places, such as shady people and areas when you're buying it, and trouble with running from the police. I would advise you to quit.