Cancer: Bad luck

Read this text (high level) and answer these questions (easier):

1. Vocabulary: random,
2. What are the three causes of cancer? What is the proportion of each cause according to this study?
3. When in the cell cycle do random mutations occur?
4. What genes must mutate to develop a cancer? (relate the information in this text with the video about cancer).
5. What is the function of the stem cells?
6. Complete this statement: “ The higher the number of stem cell divisions in a tissue, the _________________ the probability of random mutations and the ___________________the incidence cancer in that tissue”.
7. Why is colon cancer much more prevalent than small intestinal cancer in humans? Does it happen the same with mice (why)?
8. Why do lung cancer and skin cancer have higher risk than predicted by the number of stem cell divisions?
9. Are healthy habits important when it comes to cancer?
10. Draw a conclusion you could explain to 10-year-old children.
11. All these conclusions are based on an statistical model:scientists worked out cancer risk by relating the incidence of different cancers among Americans to the number of stem cell divisions of an specific tissue . What science studies statistics?