Please answer all questions

13. Which of the following statements about cancer is (are) false? Viruses can cause some cancers. (a) (b) (c) Tobacco use is responsible for more than 20% of all cancer deaths. A mutation in even a single cancer-critical gene is sufficient to convert a normal cell into a cancer cell. Chemical carcinogens cause cancer by changing the nucleotide sequence of DNA. (d) 14. Which one (ones) of the following genetic changes convert(s) a proto-oncogene into an oncogene? (a) (b) (c) (d) A mutation that introduces a stop codon immediately after the codon for the initiator methionine. A mutation within the coding sequence that makes the protein hypoactive. An amplification of the number of copies of the proto-oncogene, causing overproduction of the normal protein. A mutation in the promoter of the proto-oncogene, causing the normal protein to be transcribed and translated at an abnormally high level. 15. Which of the following statements about tumor suppressor genes is (are) false? (a) Gene amplification of a tumor suppressor gene is more dangerous than gene amplification of a proto-oncogene. (b) (c) (d) Cells with one functional copy of a tumor suppressor gene will usually proliferate faster than normal cells. Inactivation of tumor suppressor genes leads to enhanced cell survival and proliferation. Individuals with only one functional copy of a tumor suppressor gene are more prone to cancer than individuals with two functional copies of a tumor suppressor gene. 16. (0.2) Match the four lettered lines in Figure below with the appropriate numbered label. A 1. integrin 2. actin 3. collagen 4. fibronectin B plasma membrane adaptor- proteins D Page 3 of 5 extracellular space cytosol