Basic and Clinical Sciences (BCSE) Practice Exam

Carcinogens in tobacco primarily operate through the mechanism of DNA damage. Tobacco smoke contains numerous harmful chemicals, including polycyclic aromatic hydrocarbons, nitrosamines, and other metabolites that directly interact with cellular DNA. These carcinogens can induce mutations by forming adducts with DNA, leading to alterations in the genetic code. Such mutations can disrupt normal cell cycle regulation and promote uncontrolled cell growth, a hallmark of cancer development.

Understanding this process is crucial because it highlights the role of tobacco use in increasing the risk of various cancers, including lung, throat, and mouth cancers. The focus on DNA damage as a mechanism emphasizes the importance of preventing exposure to tobacco and implementing cessation programs to reduce cancer risk in populations.