Dystrophin. It is the protein located between the sarcolemma and the outermost layer of myofilaments in the muscle fiber. It is a cohesive protein, linking actin filaments to another support protein that resides on the inside surface of each muscle fiber's plasma membrane.
It is pulling your foot away after stepping on a sharp object
Avoiding drug use in the first place would be learning about the negative effects drugs have on your mind and body. Avoid situations where peer pressure might be a main factor in you doing drugs. Some barriers that might come up while trying to avoid using drugs would be as previously mentioned, peer pressure situations. If you have an addictions, you might have trouble stopping due to withdrawal symptoms which can cause you to lose control of yourself. Rehab is a great option for people struggling with addiction because it's a drug-free environment.
Genetics of course :D
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