Exam 14: Gene Mutation, Dna Repair, and Transposition

In general, mutation rates in humans are _.

What is the Ames test, and how does it work?

Assuming one mutational event in a gene, on average, which of the following mutagens or mutational conditions would be expected to cause the most damage to a protein synthesized by such a mutagenized gene: 5 -bromouracil, 2 -amino purine, ethylmethane sulfonate, or frameshift?

IS elements (insertion sequences) are stable DNA occupants of prokaryotic genomes that are not found among eukaryotes.

Strand discrimination during the process of DNA repair is based on DNA methylation in E. coli.

One type of mutation involves the replacement of a purine with a purine, whereas another causes the replacement of a pyrimidine with a purine or the reverse. What general terms are associated with these two mutational phenomena?

How were insertion sequences (IS elements) first discovered?

Describe the action of the enzyme transposase.

What are LINES?

Under certain conditions, the rate of mutation of a particular gene may be fairly easy to determine. Name three properties of the mutation that would favor the most direct determination of mutation rate.

Recent discoveries on causes of fragile -X syndrome, myotonic dystrophy, and Huntington Disease indicate which type of genetic alteration?

Three human disorders-fragile -X syndrome, myotonic dystrophy, and Huntington disease-are conceptually linked by a common mode of molecular upset. Describe the phenomena that link these disorders.

Assume that a new mutation occurs in the germ line of an individual. What finding would suggest that the new mutation is dominant rather than recessive?

Mutations that arise in nature, from no particular artificial agent, are called _.

Pyrimidine dimers are typically caused by the mutagen 2 -amino purine.

How was it determined that X rays are mutagenic?

Which of the following name two mutagens that would be classified as base analogs?

Describe the mutagenic action of the following two mutagens: 5 -bromouracil and ultraviolet light.

A mutation that occurs naturally, without exposure to a known mutagen, is called a(n) ________.

2 -amino purine is an alkylating agent.