By Anne Marie Helmenstine, Ph.D. Combustion Definition: Combustion is a chemical reaction chemical that occurs between a fuel and an oxidizing agent that produces energy, usually in the form of heat and light.Related Articles.ombustion Definition: Combustion is a chemical reaction chemical that occurs between a fuel and an oxidizing agent that produces energy, usually in the form of heat and light. Related Articles.
It is important to note then that whether a person decides to use alcohol or drugs is a choice, influenced by their environmentâpeers, family, and availability. But, once a person uses alcohol or drugs, the risk of developing alcoholism or drug dependence is largely influenced by genetics.Alcoholism and drug dependence are not moral issues, are not a matter of choice or a lack of willpower.hen an animal eats a certain food that it likes, there is an advantage to associating pleasure with that food so that the animal will look for that food in the future. In other words, the genetic potential for addiction is hardwired into our brain. But some people are better at knowing when enough is enough.
The Role of Family History. Addiction is due 50 percent to genetic predisposition and 50 percent to poor coping skills. This has been confirmed by numerous studies. One study looked at 861 identical twin pairs and 653 fraternal (non-identical) twin pairs. When one identical twin was addicted to alcohol, the other twin had a high probability of being addicted. But when one non-identical twin was addicted to alcohol, the other twin did not necessarily have an addiction. Based on the differences between the identical and non-identical twins, the study showed 50-60 percent of addiction is due to genetic factors.(1) Those numbers have been confirmed by other studies.(2) The other 50 percent is due to poor coping skills, such as dealing with stress or uncomfortable emotions.