Does smoking help protect the joints?
http://www.cnn.com/2011/HEALTH/07/08/smoking.protect.joints/index.html

Research has shown that people who smoke are less likely to need joint-replacements. Scientists conducted a study of older men in Australia and showed that the longer they smoked, the less likely they were to need a replacement surgery. However, it is unclear why this is the case, although scientists believe it may have something to do with the nicotine, which is the chemical that makes tobacco so addictive. Nicotine may stimulate activity in cartilage cells, and by doing so weaken the severity of arthritis. Despite this, scientists still do not recommend smoking, as the harms still outweigh the potential benefits. They are instead hoping that further research will help them figure out exactly how smoking helps prevent damage to joints so they can develop treatments that do not involve smoking.
This article is related to what we are learning in Honors Biology because it is about the respiratory system, and the skeletal system. We have learned about smoking, and all the problems it causes like cancer and heart disease. We have also learned about nicotine, the chemical that addicts people to smoking. Smoking is related to the respiratory system because it usually damages tissue in the lungs and prevents them from working as well, causing homeostatic imbalance. The part about fewer joint problems involves a different topic we studied; the skeletal system. We studied how joints work and how cartilage is essential to their function. We also learned about arthritis and other diseases that damage the joints.