FINAL EXAM
which of the following would not be consistent with the idea that a human disease has a genetic component -It has a particular age of onset. -It is less likely to occur in relatives living apart than in relatives living together. -A correlation is found between the presence of a mutation in a particular gene and the occurrence of the disease. -all of above
-It is less likely to occur in relatives living apart than in relatives living together.
Which of the following is not a mutagen that can cause induced mutations -5bromouracil used for chemo -uv light -tautomeric shift that cuases mis-base pairing -a chemical such as nitrous acid that can change the structure of a bas
-a tautomeric shift
Gene X can exist as a normal allele and also as a dominant mutant allele that causes a disease. You purify protein X from a homozygous normal individual and also from an individual that is homozygous for the mutant allele. You have an assay to determine the function of protein X. When you assay 1 mg of the purified protein from a normal homozygote, the activity is 100%. When you mix together 0.5 mg of the normal protein and 0.5 mg of the mutant protein, the activity is 13%. Based on this experiment, why type of dominant mutant is this? - dom neg - hapoloinsuff -dominant negative and haploinsufficiency -gain of function
-dominant negative
gene knockout is a gene -whose function has been inactivated that has been transferred to a diffrent species -that has been moved to a new location in the genome 0that has been eliminated from a species during evolution
-function has been incativated
BLAST program begins with a particular gene sequence and -translates it into an aa sequence -identifies homologues within a database -determines if it contains one or more genes -does all of the above
-identifies homologues with database
DNA microarray is a slide that is dotted wtih -mRNAs from a sample of cells -Fluorescently labeled cDNA -known sequences of DNA -known cellular proteins
-known sequences of DNA
What is the key reason why A and B chains of insulin are made as fusion proteins with beta galactosidase? -to make purification easier -to prevent degradation -to be secreted from the cell -all of the above
-to prevent degradation
A gene exists as two alleles designated D and d. if 48 copies of gene are the D allele and 152 are the d allele, what is the allele frequency of D
.24
Differences between doubles trand break model and holliday model: -how dna strands are broken -initial intertwining -formatin to appropriate beings
DSB: both strands in the same chrmatid are cut: initiation of D loop formation by uncut strands HM: one strand of each homologous chromotid is cut at similar potints which is the formation of holliday junction -dsb: intertwined by forming a d loop in between the homologous chromatids HM: intertwining of complementary strands of 2 homologs with similar chromatids occur (x shaped connection if formed) DB: once d loop forms, it does not migrate from area that it eas made HM: once made, it migrates to the opposite end of the leading strand... leads to complete reversal of base pairs
during real time pcr, the synthesis of PCR products is analyzed
during the PCR cycles by fluorescence that is emitted within the thermocycler.
tumor suppressor genes can promote cancer when -they are overexpressed -they are expressed in wrong cell type -the function is inactivated -they are expressed in wrong development stage
function is inactivated
which of the following is not a common way to eliminate the function of a tumor suppressing gene? -mutation in gene itself -incrase in chromosome number -chromosome loss -dna methylation
increase in chromosome number
in reverse transcriptase PCR, the starting bio mateial is
mRNA
One way to determine if a segment of chromosomal DNA has been inserted into a vector is to put XGal in the growth media. Following overnight growth, white colonies contain...
vector with inserted fragement of chormosomal DNA; the lacZ gene has been inactivated
The rb gene encodes a protein that inhibits E2F, a transcription factor that activates several genes involved in cell division (see Figure 25.14). Mutations in rb are associated with certain forms of cancer, such as retinoblastoma. Under each of the following conditions, would you expect cancer to occur? -One copy of rb is defective; both copies of E2F are functiona -both copies of rb are defecgive. both copies of e2f are functiona -bth copies f rb are defective. one e2f active -both copies of both genes are defective
- cancer may occur. another mutation of rb is needed to cause cancer -cancer. nothing to stop e2f -cancer. -no cancer
homologous genes -are derived from teh same ancestral gene -are likely to carry out the same or similar functions -hve similar DNA sequences -exhibit all of the above features
-all the above
which of the following methods is not used to study the level of RNA synthesis in a sample of cells at the genomic level -chromatin immunoprecipitation -RNA seq -DNA microarray
-chormatin immunoprecipitaitn
For the method of RNA sequencing how do you order the following -synthesize cDNAs -isolate RNAs -align cDNA sequences -fragment RNAs -seuquence cDNAs
-isolate RNAs -fragment RNAs -synthesize cDNAs - sequence cDNA -align cDNA sequences
which of the following is a factor that, by itself, does not promote widespread changes in allele or genotype frequency? -natural selection -genetic drift -nonrandom mating -new mutation -migration
-new mutation
which of the following would not convert a protooncogene to an oncogene? - gene amplification - translocation - promoter deletion - missense mutation
-promoter deletion
Which of the following statements regarding retrotransposons is false? -some are similar in structure to known viruses -retrotransposons are most abundant in genomes of complex multicellular eukaryotes -retrotransposons require reverse trnscriptase to be inserted into a new site -retrotransposons are commonly found in prokaryotic genomes
-retrotransposons are commonly found in prokaryotic genomes
BLAST program begins with query sequence and -uses search by signal approach to identify genes that are homologous to query searcy -uses a search by signal approach to determine if a DNA sequence contains one or more genes. -searches a database to identify genes that are homologous to the query sequence. -searches a database to determine if a DNA sequence contains one or more genes.
-searches a database to identify genes that are homologous to the query sequence.
would a program use sequence recognition, pattern recognition or both? -segment of drosophila DNA contains a p element (specific type of transposable element_ -whether segment f DNA contains stop codon: -inverted segment -whether log segment of bacterial DNA contains one or more genes.
-sequence since the p elements is already known (i think you can use pattern recognition too) -sequence recognition. there are three different stop codons that are made up of specific three base sequence. A program would be given info with these three sequences and would scan the sequence file to identify a perfect match regarding as top codon -inversion: pattern recognition -search by signal approach: both sequence and pattern recognition.. looks for organization of sequence elements that would ofmr functional gene. search by content approach identifies genes based on patteerns. looks for a pattern in which the nucleotide content is different from a random mutation?? or scan the gene sequence for long open reading frames..???
most forms of cancer involve -activation of single oncogene -the activation of multiple oncogenes and the inactivation of multiple tumor suppressor genes -the activation of multiple oncogenes - the inactivation of a single tumor suppressor gene
-the activation of multiple oncogenes and the inactivation of multiple tumor suppressor genes
the allele frequency of C is 0.4 and c is 0.6. if the population is in the Hardy weinberg equilibrium, what is the frequency of the heterozygote?
0.48
Which is the proper order of the following steps in a gene cloning expierment involving vectos?? 1.) add dna ligase 2.) incubate the chomrosomal DNA and the vector DNA with a restriction enzyme 3.) introduce the dna into living cells 4.) mix the chromosomal DNA and vector DNA together
2, 4, 1, 3
a mutagen that is a base analog is -ethyl methanesulfonate -5 bromouracil -UV light -proflavin
5 bromouracil
what would each of the following mutations cause? (transition, transversion, frameshift?) why? 5-bromouracil nitrous acid proflavin
5-bromouracil: transition because they are base analoges that are incorporated into daughter strands. bromouracil is thimine analog so it can still pair with adenine (but it can also cause transversion because at high rate 5BU undergoes tautomeric shft and base pairs with guanine. nitrous acid: transition because it replaces amino groups iwth keto groups which is deamination which changes cytosine to racil and adenine to hypoanthine they pair differently than original bases??? proflavin: frameshift apparently. flat struvture that intercalates or inserts itself between adjacent base pairs which distorts the helical structure... somehow this causes a transition? not sure oH BECUASE IT INSTERTS BETWEEN BASE PAIRS
Reproductive cloning is a method of using the genetic material from somatic cells to produce offspring that are gentically identical to the donor parent. how does this work? - A somatic cell, such as a mammary cell, has its nucleus removed and then the nucleus from an oocyte is inserted into it. -A somatic cell, such as a mammary cell, is made totipotent by treating it with hormones. -A sperm and egg cell are fused with a somatic cell (e.g., a mammary cell) that had its nucleus removed. -A somatic cell, such as mammary cell, is fused with an egg cell that had its nucleus removed.
A somatic cell, such as mammary cell, is fused with an egg cell that had its nucleus removed.
A gene exists in two alleles, D and d. The gene is 2066 bp in length, and the B and b alleles exhibit single base pair differences at 8 different sites that are very close together. Let's suppose that gene conversion changed the D allele into the d allele. Which mechanism would you favor to explain the conversion—mismatch repair or gap repair synthesis? Explain your choice.
Gap repair. there can be a repair of multiple base pairs at the right location. with mismatch repair, there can be conversion of the gene or no conversion (50/50 chance). with gap repair synthesis, in this case the nucleotides that encode the D allele would be degraded and with strand inversion and a D loop, the d allele would be synthesized in the place where the D allele was located.
why does the movement of retrotransposons, called retroelements produce direct repeats on both sides of the retrotransposon? -integrase inserts repeats at both ends of the transposable element -integrase makes staggered cuts that are filled in by DNA repair synthesis -Integrase causes one of the two inverted repeats to flip to the opposite direction -b and c
INTEGRASE MAKES STAGGERED CUTS THAT ARE FILLED IN BY DNA GAP REPAIR.
how may gene conversion occur? gap repair synthesis nucleotide exision repair mismatch repair
Mismatch repair gap repair synthesis
How would a mutation that prevents the Ras protein from hydrolyzing GTP affect the EGF signaling pathway and how would it affect cell growth? - The signaling pathway would stay turned on and cell growth would be stimulated. -The signaling pathway would stay turned on and cell growth would be inhibited. -The signaling pathway would be turned off and cell growth would be inhibited. -The signaling pathway would be turned off and cell growth would be stimulated.
The signaling pathway would stay turned on and cell growth would be stimulated.
which of the following is not an example of a spontaneous mutation -error in DNA replication -tautomeric shift -UV light -all of above
UV light
double strand breaks can be repaired by -homologous recombination repair -nonhomologous end joining -nucleotide excision repair -both A and B
a and b
advantages and disadvantages of mutations
advantage: form new alleles (new traits and phenotypes) disadvantage: they can cause disease
advantage and disadvantage of TRP (translesion replication polymerases)
advantage: they can replicate over damaged DNA but they have low fidelity.
which of the following is a type of genetic change that could produce an oncogene -missense mutation -gene amplificatin -chromosomal translocation
all
Which of the following uses of microorganisms is/are importnat for biotechnology -productin of meds -food fermentation -biological control -all of above
all of above
genetic drift is -a change in allele frequency due to random fluctuatins -likely to result in allele loss or fixation in the long run -more pronounced in smaller populations
all of above
point mutation can be caused by: -depruniation -deamination -tautomeric shift -all of above
all of above
personalized medicine may be used -to characterize types of tumors -to preduct the outcome of certain types of cancers -to determine the proper dosage of drugs -all of above
all of the above
which of the following DNA repair systems may involve the removal of a segment of a DNA strand? -base excision repair -nucelotide excision repair -mismatch repair
all of the above
a gene pool is
all of the genes in a population of individulas
a gene exists in two alleles, and the heterozygote has the highest fitness. this situation is likely to result in
balancing selection
one strategy for producing a protein in the milk of a cow is to place the ocding sequen ce of the gene of interest next to___ and then injecting te gene into a ______ -lac operon, oocyte -b lactoglobulin promoter, oocyte -lac operon, mammary -beta lactoglobulin, cow mammary
beta lactoglob promoter, oocyte
which is not a common explainatino for a dominant disorder -haploinsufficiency -gain of function mutation -dominant negative mutation -change in chromosome number
change in chromosome number
The restriction enzymes used in gene-cloning experiments _____ DNA which generates sticky ends that can ________-
cut, hydrogen bond with complementary sticky ends
nitrous acid replaces amino groups with keto groups, a process called
deamination
Whatis the correct order of steps in one PCR cycle
denaturization, primer annealing, primer extension
wihtin a particular population, darkly colored rats are more likely to survive than more lightly colored individuals. This situation is likely to result in .....
directional selection
population occurs in heterogeneous environments in which the fitness of some genotypes is higher in one environment and the fitness of other individuals is higher in nother envionrment. this is likely to result in
disruptive selection (diversifying selection)
Which of the following mechanisms can cause gene conversion (two)
dna mismatch repair, DNA gap repair
what is dominant negative mutations
dominant disorders that are characerized by dominant negative mutations in which the gene product acts antagonistically to the normal gnee product
For a genetic disease that is equally probable in females and males, the concordance value for identical twins is 91% and for fraternal twins it is 45%. Do these concordance values suggest a recessive or dominant pattern of inheritance? Provide two reasons why the concordance value between identical twins is not 100%
dominant. punnett square shoes the offspring that would occur between a homozygous (no disease) and a heterozygous (for disease) if teh disease was dominant, than 50% of offspring would have the disease. 45% is close to 50% -disease occurs due to mutation to the genome that occurred after fertilization -another reason could be that the disease penetrance was low so there would be no phenotypic abnormality
When a cloned gene is inserted into a noncritical site in the mouse genome by homologous recombination, the result is (additin or modificaiton)
gene addition
A collection of recombinant vectors that carry fragemnts of chromosomal DNA is called: -genomic library -cDNA library -a northern blot -a or b
genomic library
One way that TNRE may occur involves the formation of _____ that disrupts _____
hairpin, DNA replication
is a rando mutation more likely to be harmful or beneficial
harmful. mutations within coding sequences can produce early stop codons, missense mutations, or frameshift mutations that can result in a polypeptide that is not functional
During the molecular process of homologous recomination between homologous chromosomes, what three things happen
holliday junction, branch migration, heteroduplex region forms
the alpha globin gene in humans and alpha globin gene in mice can be described as -homologs -orthologs -paralogs
homologs and orthologs
a mutation in one gene that reverses the phenotypic effects of a mutation in a different gene is a -intergenic suppressor -intragenic suppressor -an up promoter mutation -a position effect
intergenic suppressor
locus heterogenicity refers to a genetic disorder that
is caused by mutations in two or more different genes
When gene knockin is made in mice, the gene of interest _____. This is an example of _______- -is inserted into a noncritical site in the genome, gene addition -is swapped with an endogenous gene, gene addition -is inserted into a noncritical site in the genome, gene replacement -is swapped with an endogenous gene, gene replacement
is inserted into a noncritical site in the genome. gene addition
what is the role of uvRD
it is a helicase that removes the damaged region
down promoter mutation causes the promoter of a gene to be _____ like the consensus sequence and ______ transcription
less, inhibits
what is the role of UvrC in nucleotide excision repair
make cuts on either side of the lesion
During homolgoud recombination, how is a heteroduplex formed? -by the initial breakage f the DNA at a single location in two different DNA strands -by the migratin of a holliday junction -by the resolution of the holliday junction into two separate DNA strands -by the formatin of a D loop
migratin of holliday junction
a mutatin that changes a serine codon to an arginine codon is what kind of mutation
missense mutation
Lets suppose a chemical is a mutagen, if you tested this chemical usigng the AMES test, there will be _____ colonies on the plates in which the cells had been exposed to the mutagen because the mutagen converts some of the cells from ___ to _____
more, his- to hhis +
normal (nonmutant) tumor-suppressor genes often function -as negative regulators of cell division -in maintenance of genome integrity -the stimulation of cell division
negative regulators maintenance of genome integrity
a mutation changes a codone that specifies tyrosine into a stop codon. this type of mutation is a
nonsense
Which method uses a labeled nucleic acid probe? (western or nothern)
northern
which method is used to detect specific RNA within a mix of different RNAs?
northern
what is haploinsufficiency? is it found in dominant or recessive
phenomenon in which a person has only a single functional copy of a gene and the single functional copy does not produce a normal phenotype (50% of the functional protein is not sufficient to produce a normal phenotype).
Which of the following may be used as a vector in gene-cloning experiment: -pasmid -mRNA -virus
plasmid and virus
in natural populations, most genes are: -recessive -monomorphic -polymorphic -both a and c
polymorphic
An oncogene is produced from a ______ that has aquired a _____ of function mutation
proto-oncogene, gain
Darwinian fitness is a measure of
reproductive success
Which transposable elements rely on an RNA intermediate for transposition
retrotransposons
identification of stop codon for a particular gene is an example of: -sequence recognition - pattern recognition - a and b - neither
sequence rec
An original DNA strand had the sequence, 5'-ATG_GGA_CTA_GAT_ACC-3'. what are the following mutations called A. 5'-ATG_GGT_CTA_GAT_ACC-3' B. 5'-ATG_CGA_CTA_GAT_ACC-3' C. 5'-ATG_GGA_CTA_GTT_ACC-3' D. 5'-ATG_GGA_CTA_AGA_TAC_C-3'
silent missense missense frameshift
homologous recombination refers to the exchange of DNA segments that are
similar or identical in their DNA sequences
why is it useful to search a database to identify sequences that are homologous to a newly determined sequence
since homologous genes are derrived from the sam ancestral gene, there is a strong correlation between homology and function. When there is a newly determined sequence, searching for homologues can reveal improtant information about the particular function of agene
During mammalian reproductive cloning, ____ is fused with ________
somatic cell, ENUCLEATED egg cell
what is a gain of function mutations and is it dominant or recessive
such mutations change the gene product so it gains a new or abnormal function
key difference bewteen original holliday model and the double strand break model is the way that
the DNA strands are originally broken
which of the following would not be consistent with the idea that a disorder has a genetic component -the disorder can be spread to individuals sharing similar envionrmnts -more likely to occur among an affected persons relatives than in gen pop -correlation between d/o and mutatn gene -tends to develop at characteristic age
the disorder can be spread to individuals sharing similar environments
which of the following is an example of a somatic mutation -mutation in embryonic muscle cell -mutation in sperm cell -mutation in adult nerve cell.
the embryonic muscle cell and the adult nerve cell.
during western blotting, the primary antibody recognizes
the protein of interest
purpose of Chip assay is to determie -expression levels of particular genes in genome -the sites in a genome where a particular protein binds. -the amount of a specific protein that is made in a given cell type -any of the above
the sites in the genome where a particular protein binds
When a dideoxyribonucleotide is incorporated into a growing DNA strand,
the strand cannot elongate
According to selfish DNA hypothesis, TEs exist because
they have characeristics that allow them to multiply within the chromosomal DNA of living cells
what are the two key features of stem cells
they have the ability to divide and differentiate
function of photolas is to repair
thymine dimers
what is the funciton of uvrA and uvrB
to detect DNA damage
the function of transposase is (3)
to recognize inverted repeats, to remove TE from original site, to insert TE into a new site
What is the protein that is used by a transposon which is a transposable element that moves via a segment of DNA
transposase
How are a or b chains in production of insulin separated from beta galactosidase?
treatment iwth cyanogen bromide
what determines the stability of sticky ends?
unknown to me.. the regions in between are mostly comprised of AAAandTTT are less stable? ? just what i think tho.
