BIOL 2500 chapter 19 mc
after screening a colony of bacteria for mutations in a given gene, you discover 100 mutant colonies out of 3 million total colonies. what is the mutation frequency for this gene in the population?
3.3x10^-5
an example of a base analog would be
5BU
most TNRE repeats involved expansion of which codon?
CAG
spontaneous mutations include
Depurination, deamination, errors in DNA replication
which repair mechanism often leads to deletions in chromosomes
NHEJ
anticipation is associated with which type of mutation
TNRE mutations
example of an induced mutational mechanism
UV light
in the nucleotide excision repair system, which of the following proteins is responsible for recognizing a thymine dimer to be repaired?
UvrA/UvrB
a temporary change in the conformation of a nitrogenous base is called
a tautomeric shift
an example of a mutagen that integrates into the double-helix of DNA resulting in the inhibition of DNA replication would be
acridine dyes
a mutagen is
an agent that can alter the structure of DNA and cause mutations
the wild type eye color of drosophila is red. a single base mutation can occur that produces a white eye color.
an example of a mutation that alters protein function
an example of a suppressor mutation would be
an intragenic mutation that restores the inactive protein's structure
which DNA repair mechanism uses DNA-N-glycolases
base excision repair
the mechanism for reactive oxygen species to cause mutation is
bases are oxidized to a variety of different products which might pair with a different base than the original base would have
mutations that change the configuration of a protein at a specific temperature are called ___ mutations
conditional
the conversion of cytosine to uracil in DNA is an example of
deamination
the complete loss of either a guanine or adenine from DNA is an example of ___
depurination
photolyase in yeast is an example of what kind of DNA repair mechanism
direct repair
TNRE repeats frequently result in the addition of extra histidine amino acids to the protein
false
a change in the chromosome number is called a point mutation
false
a mutation in a promoter region that causes the promoter sequence to more closely resemble the consensus sequence is called an up promoter mutation and results in a decrease in transcription
false
an individual that is a genetic mosaic would be the result of a germ cell mutation
false
ethyl methanesulfonate is an example of a deaminating agent
false
somatic cells are those that give rise to sperm and egg cells
false
the most common genotype in a population is called the mutant genotype
false
the mutation frequency would be the same for all genes in a given culture
false
which repair mechanism identifies daughter strands by methylation
mismatch repair
which repair mechanism utilizes MutL, MutH, MutS proteins in E.coli
mismatch repair
which repair mechanism is responsible for repairing damage from UV radiation?
nucleotide excision repair
translocations and inversions may result in
position effect
a culture of E.coli bacteria is used to establish several subcultures. each subculture is then plated and individual colonies that grow on the agar plates are then tested for their sensitivity to the bacteriophage T1. there is a spectrum of sensitivities where some plates have a high number of resistant colonies and some plates had very few. this data supports which theory/
random mutation theory
the results of the replica plating experiments by the Lederbergs supported which theory?
random mutation theory
a translocation that moves a gene from an area of euchromatin to heterchromatin would typically cause a ___ in the expression of the gene
reduction
which types of mutations are least likely to be subjected to natural selection
silent
the difference between the polymerases used in translesion synthesis repair and general DNA replication is
the polymerase used in translesion synthesis has a pocket that can accommodate the lesions while DNA pol III's pocket cannot
what would be a set of anticipated results from a lederberg experiment
total # of colonies on a plate: 1500 total # of resistant colonies on replica plate with T1: 150
how does position effect influence gene expression?
translocations may result in a promoter that is normally used for one gene now controlling an entirely different gene
in the following sequence of DNA, the italicized base has been mutated. what type of mutation is this? 5' - GATCTCC"G"AATT - 3' 5' - GATCTCC"C"AATT - 3'
transversion
HRR usually uses a sister chromatid
true
a heritable change in the genetic material is called a mutation
true
a mutation in one gene that compensates for a mutation in another gene to result in the wild type phenotype is called an intergenic suppressor mutation
true
breakpoints in chromosomes can lead to mutant phenotypes when they occur in the middle of a gene
true
rates of spontaneous mutation per cell generation typicaly range from 10^-5 to 10^-9
true
silent mutations are possible due to the degenerate nature of the genetic code
true
the ames test may be used to determine if an agent is a mutagen
true
the mutation frequency for a gene is the ratio of the number of mutant genes to the total number of copies of that gene in a given population
true
the process of replica plating was designed to test if mutations occurred in response to a selective agent or if mutations were naturally present in the population before selection
true