Why does nicotine cause necroses?

Answer 1

== == I'm not sure I know what you mean by "necoses", since that is not an actual word, but I know that medical terms can be difficult to figure out, especially the spelling. It would be helpful if you would re-write the question and include what you mean by this word. I will assume, for the time being, that you are referring to "necrosis", which means that tissue in the body dies, (Necro=death; osis=condition of.) If you are referring to lung tissue or other cells in the body, smoking cigarettes doesn't actually cause tissue *death* of the little air sacs...that would mean there is rotting tissue inside the body and this would lead to severe infection, not to mention many other problems, but it *does* mean that the the air sacs and the tiny finger-like projections in the lungs (called cilia) become unable to function. (The cilia are responsible for "sweeping" unwanted material from the lungs.) It is actually the *tar* in the cigarette smoke that does most of the tissue damage, not nicotine, though nicotine does do other types of damage. The tar coats the tiny air sacs (called "alveoli") in the lungs and makes the alveoli unable to exchange the "good" air for the "bad" air, and it also makes them very stiff. It does this to the cilia as well and they become unable to rid the lungs of all the harmful build-up of the cigarette by-products. That's why so many people who have smoked for a long time usually get "emphysema", or as it's also called, chronic obstructive pulmonary disease...COPD for short. As this disease advances, a person is able to breathe in with some difficulty (because of the stiff or "dead" air sacs), but cannot push all the "bad" or "used" air out. That means they retain the carbon dioxide and other by-products of respiration that then build up in the blood stream.