I'm working on a project about smoking any thing anyone knows will

In cigarettes, there is this substance called "nicotine." This substance is the reason for addiction. It causes your brain to feel relaxed whilst smoking, then for a while after you remove the cigarette, you feel happy and relaxed. But, this doesn't continue. After a while, it stops and is replaced with feelings of nervousness, anxiety, and anger as well as many other uncomfortable emotions. 
  These emotion cause the smoker to want to relax, therefore, they grab another cigarette.
 Cigarettes are very harmful to one's body. They can cause skin cancer, lung cancer, and teeth problems. See anyone with bad yellow teeth and bad-smelling breath? It is most likely that they smoke. Though, not everyone who smokes gets sick. There is this thing called "second-hand smoking" that occurs when a person is around a smoker. It happens because the non-smoker breathes in the fumes and smoke of the cigarette the smoker is smoking. It is juts as bad as normal smoking.
  Now, you might think eCigarretes are good for you...but they are not! They cause almost- if not exactly- as much harm to your body that a normal cigarette would.
 Never try smoking. It will lead to an addiction that is neither attractive, or healthy!

Muscles in the body us with a lot of things for example, if i wanted to lift a heavy box and had no muscle i would just collapse where i was because of the fact muscles hold us together. overall they are 650 muscle in the human body, all of them have different purposes and ways to keep us together. there are three types of muscle in the body skeletal, smooth, and cardiac muscle. skeletal muscle are attached to the bone and with movement. smooth muscle, this is found in the wall of our organs, such as our stomach, this muscle with movement   as well, without this muscle, we would only be allowed to eat small amounts. the cardiac muscle is the heart muscle and probably the most important one. these are only found in the walls of the heart and the heart pump blood to the other parts of your body. we have two different types of muscle fibers, slow twitch and fast twitch. slow twitch muscles enable long-endurance feats such as distance running. fast twitch fatigue faster but are used in powerful bursts of movements like sprinting. there are three different types of muscle contractions concentric, eccentric, isometric. concentric contraction causes muscles to shorten, thereby generating force.   eccentric contractions cause muscles to elongate in response to a greater opposing force. isometric contractions generate force without changing the length of the muscle.: //athleticquickness.com/muscle-contraction-types-part-1/