Why do stem cells that have been damaged prefer apoptosis over repairing the genome?   a. Stem cells cannot repair the damaged genome b. The repair machinery is not perfect and therefore prone to make mistakes c. They don't d. None of the above

The following type of mutation in a proto-oncogene may cause cancer in human: A. Translocation of gene B. Gene amplification C. point mutation within regulatory element. D. All of the above

A scientist is interested in producing flowers with a darker red color. To do this, the scientist alters the promoter of the gene to make it more active. This results in increased transcription and increased red pigments. The scientist then alters the promoter to make it even more active. This results in white flowers with no red pigment. Genetic research showed an increase in the siRNA in the cell. What did the siRNA do to the mRNA?   A. The siRNA caused the mRNA to be broken down.   B. The siRNA caused alternative splicing of the mRNA.   C. The siRNA caused increased methylation of the mRNA.   D. The siRNA caused the ribosome to no longer recognize this mRNA.

Which of the following is true about the enzyme telomerase?   A. It is found only in adult cells.   B. It is responsible for telomere shortening.   C. It can re-establish telomere length.   D. It may speed up the aging process.   E. It is expressed at low levels in cancer cells.