Ch 16 7 Can you please answer as many as possible I need thi

Ch 16. 7>>> Can you please answer as many as possible, I need this to cross reference the answers that I got. Thank you so much for all your help.

Solution

7. Why do mutations in genes that encode DNA-repair enzymes often produce a predisposition to cancer?

B. Cancer is the result of an accumulation of mutations in tumor-suppressor genes and proto-oncogenes, and a deficiency in DNA repair can accelerate this process.

8. Both genes and environmental factors contribute to cancer. The table below shows that prostate cancer is 30 times as common among Caucasians from Utah as among Chinese from Shanghai. Briefly outline, how you might determine if these differences in the incidence of prostate cancer are due to differences in the genetic makeup of the two populations or to differences in their environments.

B. If the discrepancy in cancer rates is caused by environmental differences and not genetic makeup, then all of the people in one location should have similar cancer rates despite different ethnic backgrounds.

9. The palladin gene, which plays a role in pancreatic cancer, is said to be an oncogene. Which of its characteristics suggest that it is an oncogene rather than a tumor-suppressor gene?

C. The mutated version of palladin causes a dominant effect over the wild-type palladin alleles.

10. Mutations in the RB gene are often associated with cancer. Explain how a mutation that results in a nonfunctional RB protein contributes to cancer.

A. RB acts at the G1/S checkpoint to prevent cells from beginning DNA replication; without RB, the cell will be more likely to progress into S phase.