MCB 229 Spring 2000 Study Guide 14 Prof.
Terry
Covers Lecture for March 30
This study guide is intended for you to use while you are
doing the assigned text reading. Quiz questions will be made with reference to
topics in this study guide. Quiz #14, based on questions from this study guide,
must be completed by midnight before the class on Thursday, March 30. You will
need to create your "myWebCT" account and visit the MCB 229 WebCT page in order
to access this quiz.
Chapter 13. Microbial genetics: general
principles.
- What do each of the following terms mean: genome, haploid, diploid,
genotype, phenotype?
- What discovery did Fred Griffith make? Alfred Hershey
& Martha Chase?
- Material on pp. 258-262 was included in a previous study
guide and will not be quizzed here, except as noted below.
- What do each of
the following terms mean: mutation, conditional mutation, auxotroph, prototroph,
mutagen, spontaneous mutation, induced mutation, transition mutation,
transversion mutation, tautomeric shift, frameshift mutation?
- Can C ever
form base pairs with A? If so, what is the mechanism? Can a purine ever base
pair with a purine? A pyrimidine with a pyrmidine? If so, what is this
called?
- Using the following DNA sequence as a template, practice making an
appropriate base change to create each of the following:
a transition mutant |
a transversion mutant |
a frameshift mutant |
ATTCAGACCA
|
ATTCAGACCA
|
ATTCAGACCA
|
- How does a base analog
induce mutations? How does ethylmethanesulfonate (EMS) induce mutations? How do
acridine dyes induce mutations? How does UV light induce mutations?
- What is
meant by the following terms: wild type, forward mutation, reversion mutation,
back mutation, suppressor mutation, point mutation, silent mutation, missense
mutation, nonsense mutation?
- The study of mutants has been possibly the
single most powerful tool in understanding the mechanics of life. Isolating a
desired mutant is often challenging, however, because of the rarity of
mutations. Spontaneous mutation frequencies in bacteria are roughly one per
______ cells; even with induced mutations the frequency is only about one per
_______ cells. A number of ingenious schemes have been devised that select for
certain types of mutants. The following questions address these selection
strategems.
- What is replica plating? For what type of mutant selection is
this useful?
- How would you isolate a bacterial mutant resistant to an
antibotic? Resistant to a bacterial virus (phage)?
- What does the Ames test
test for? What bacteria are used, and what properties do they have? Does the
Ames test measure carcinogenicity? If not, what does it measure? What
modification to the test is necessary in order to detect some carcinogens such
as aflatoxins?
- What is excision repair? Roughly how many bases are removed
during this proces? What enzymes are necessary for this process?
- What is
photoreactivation? How does it differ from excision repair?
- How does
recombination repair differ from excision repair? What is required in order for
this system to work?
- What is SOS repair? Under what conditions is it
active? How does it differ from excision repair?