EXAM 4 QUIZ QUESTIONS
Which process is used to replicate DNA that contains distortions due to unrepaired DNA damage? A. Translesion synthesis B. Nonhomologous end joining C. Nucleotide excision repair D. Homologous recombination repair
A. Translesion synthesis
What is the difference between the trithorax (TrxG) and polycomb (PcG) complexes of proteins? A) Methylation of H3 on lysine 27 can result in activation of transcription B) TrxG complex proteins activate gene expression by methylating lysine 4 on H3, while PcG complex proteins repress gene expression by methylating lysine 27 on H3. C) Methylation of lysine at position 4 on H3 results in silencing of gene expression D) TrxG proteins methylate lysine 27 on histone H3 while PcG complexes methylate lysine 4 on H3
B) TrxG complex proteins activate gene expression by methylating lysine 4 on H3, while PcG complex proteins repress gene expression by methylating lysine 27 on H3.
What gene is most responsible for X-chromosome inactivation? A) Xce B) Xist C) Xic D) Tsix
B) Xist
You are analyzing a human pedigree for a new disease and discover that the disease occurs with the same frequency in both sexes and that 25% of the children from two unaffected heterozygous parents have the disease. This disease is displaying ____ inheritance. A) sex-linked dominant B) autosomal recessive C) sex-linked recessive D) autosomal dominant
B) autosomal recessive
Following mitosis, the two daughter cells usually have __________ pattern of facultative heterochromatin and __________ pattern of constitutive heterochromatin as was present in the mother cell. A) a different; the same B) the same; the same C) a different; a different D)the same; a different
B) the same; the same
How many promoters are in an operon? A. 3 B. 1 C. It depends on how many genes there are in the operon D. 2
B. 1
If the Trp codons in the trpL gene were mutated to encode another amino acid, what would the result be? A. The trp operon would only be transcribed when tryptophan in the cell was high. B. The trp operon would never be transcribed. C. The trp operon would always be transcribed. D. The trp operon would only be transcribed when tryptophan in the cell was low.
B. The trp operon would never be transcribed.
What genes appear to be controlled by the Xic? A. Xist B. Xist and Tsix C. TsiX D. Xic
B. Xist and Tsix
A temporary change in the structure of a nitrogenous base is called ______. A. depurination B. a tautomeric shift C. deamination D. None of the answers are correct.
B. a tautomeric shift
Which technique can be used at the earliest stage in a pregnancy to provide a sample for fetal genetic testing? A. amniocentesis B. chorionic villus sampling C. Both chorionic villus sampling and amniocentesis are performed at the same stage in a pregnancy.
B. chorionic villus sampling
The term that refers to the linkage of alleles or molecular markers along a single chromosome is A) loss of variation. B) association group. C) haplotype. D) recombination group.
C) haplotype.
Genomic imprinting is a result of A. nucleosome location. B. histone activation. C. DNA methylation. D. serine to leucine changes in the genetic code.
C. DNA methylation.
How would a mutation that increases the rate of GTP hydrolysis by the Ras protein affect the EGF signaling pathway and how would it affect cell growth? A. The signaling pathway would stay turned on and cell growth would be inhibited. B. The signaling pathway would stay turned on and cell growth would be stimulated. C. The signaling pathway would be turned off faster and cell growth would be inhibited. D. The signaling pathway would be turned off faster and cell growth would be stimulated.
C. The signaling pathway would be turned off faster and cell growth would be inhibited.
The regulation of protein function, not gene expression is called ______ regulation. A. translational B. transcriptional C. posttranslational D. posttranscriptional
C. posttranslational
A gene is inducible and under negative control. Which of the following pairs will allow expression of this gene? A. activator + inhibitor B. activator + repressor C. repressor + inducer D. repressor + corepressor
C. repressor + inducer
What is the gene responsible for attenuation in the trp operon? A. trpR B. trpD C. trpL D. trpC
C. trpL
Mutations that change the configuration of a protein at a specific temperature are called ____ mutations. A.deleterious B.beneficial C.conditional D.neutral
C.conditional
Which types of mutations are least likely to be subjected to natural selection? A. Insertion B. Nonsense C. Missense D. Silent
D. Silent
Which of the following is found in an operon? A. promoter B. terminator C. two or more genes D. operator E. All of the answers are correct.
E. All of the answers are correct.
Which of the following is not an example of a cause of a spontaneous mutation? A. aberrant recombination B. transposable elements C. DNA replication errors D. tautomeric shifts E. UV light
E. UV light
What process repairs damage from UV radiation? A. direct repair B. base excision repair C. nonhomologous end joining (NHEJ) D. homologous recombination repair E. nucleotide excision repair
E. nucleotide excision repair
Which DNA repair process utilizes MutL, MutH, and MutS proteins in E. coli? A. nucleotide excision repair B. direct repair C. nonhomologous end joining (NHEJ) D. base excision repair E. homologous recombination repair F. mismatch repair
F. mismatch repair
Enzymes involved in metabolism are most likely regulated via _____. a. feedback inhibition b. acetylation c. methylation d. None of the answers are correct.
a. feedback inhibition
Where is the IRE located in the regulation of ferritin translation? A) 5′ end of mRNA B) 5′ end of DNA C) 3′ end of mRNA D) 3′ end of DNA
A) 5′ end of mRNA
Antisense RNA does which of the following? A. binds to a complementary RNA and prevents its translation B. occupies the A and P sites of the ribosome C. inhibits the formation of the open complex in transcription D. prevents the correct folding of a newly formed peptide
A. binds to a complementary RNA and prevents its translation
A gene that promotes the development of cancer when it sustains a gain-of-function mutation is called a A. proto-oncogene B. tumor suppressor gene. C. housekeeping gene. D. caretaker gene.
A. proto-oncogene
The results of the replica plating experiments by the Lederbergs supported which of the following theories? A. random mutation theory B. physiological adaptation theory C. both theories D. neither theory
A. random mutation theory
CAP affects which operon(s)? A. the lac operon B. the trp operon C. both the lac and the trp operon D. neither the lac nor the trp operon
A. the lac operon
Which of the following integrate into the double-helix of DNA, interfering with DNA replication? A.acridine dyes B.5BU C.nitrous acid D.EMS
A.acridine dyes
In Jacob, Monod, and Pardee's experiment, how many functional copies of lacI were there in the merozygote? A. 2 B. 1 C. 3 D. 0
B. 1
Which DNA sequence would also work in place of the following bi-directional enhancer? 5' GTTC 3' 3' CAAG 5' A. 5' CTTG 3' 3' GAAC 5' B. 5' GAAC 3' 3' CTTG 5' C. 5' CAAG 3' 3' GTTC 5' D. 5' CTTC 3' 3' GAAG 5'
B. 5' GAAC 3' 3' CTTG 5'
The general function of the p53 protein could be described as A. a negative regulator of cell division. B. maintaining genome integrity C. a positive regulator of cell division.
B. maintaining genome integrity.
What would be the result if the U-rich sequence after the fourth stem loop in the trp operon was replaced by a UG-rich sequence? A. Attenuation would occur if tryptophan was high. B. Attenuation would occur if tryptophan is low. C. Attenuation would not occur if tryptophan was high. D. None of the answers are correct.
C. Attenuation would not occur if tryptophan was high.
Which of the following is not an example of translational regulation in prokaryotes? A. Binding of antisense RNA to mRNA B. Altering the structure of the mRNA C. Phosphorylation of an enzyme D. Sterically blocking the ribosome
C. Phosphorylation of an enzyme
In a particular E. coli strain, a mutation in the thiMD operon results in improper formation of the stem loop secondary structure making it impossible to bind TPP. There are two enzymes encoded by the thiMD operon. How many of the enzymes encoded in the thiMD operon are translated? A. One B. Zero C. Two D. Three
C. Two
A translocation that moves a gene from an area of euchromatin to heterochromatin would typically cause _____ in the expression of the gene. A. no change B. an increase C. a reduction
C. a reduction
The process of _______ removes amniotic fluid from a pregnant mother to examine fetal cells for genetic problems. A. chorionic villus sampling B. in vitro fertilization C. amniocentesis D. preimplantation genetic diagnosis
C. amniocentesis
Caspases are active during which of the following? A. viral integration B. the normal cell cycle C. apoptosis D. DNA replication
C. apoptosis
Epigenetic inheritance may occur at which of the following stages? A) Oogenesis B) Spermatogenesis C) Embryogenesis D) All of the answers are correct.
D) All of the answers are correct.
For a single-gene disorder, the concordance among monozygotic twins should be A. 75%. B. 50%. C. 0%. D. 100%. E. 25%.
D. 100%.
What stem-loop conformations favor attenuation in the trp operon? A. 1-2 and 2-3 B. 2-3 C. 1-2 D. 3-4
D. 3-4
Which of the following would indicate that a disease has a genetic, rather than environmental, cause? A. The disease is cured by taking an antibiotic. B. The disease occurs as frequently between close relatives as it does in unrelated individuals. C. The disease occurs at the same rate in individuals that are exposed to a similar environment. D. The disease has a specific age of onset.
D. The disease has a specific age of onset.
The term that indicates that cancer has begun to migrate to other parts of the body is ______. A. malignant B. invasive C. clonal D. metastatic E. benign
D. metastatic
What is the molecular mechanism for imprinting a gene? A. Nitration B. Phosphorylation C. Acetylation D. Methylation
D.Methylation
One difference between developmental and environmental epigenetic changes is that A)developmental epigenetic control is a normal process that occurs in all offspring. B)environmental epigenetic control is the result of developmental processes interacting with the environment. C) the differences between the two lie in the mechanisms that each uses. D)environmental epigenetic control is a normal process that occurs in all offspring.
A) developmental epigenetic control is a normal process that occurs in all offspring.
A deletion in an operon removes the promoter. How will that affect the transcript that is produced from the operon? A. The transcript will not be produced B. The transcript will be produced, but shorter than normal C. The transcript will produced, but will contain a deletion D. The transcript will be produced, but longer than normal E. The transcript will be produced and normal in length
A. The transcript will not be produced
In the Jacob Monod merozygote experiment, what was indicated by the presence of a yellow color when b-ONPG was added? A. The lac operon was completely turned off. B. The researcher added too much b-ONPG. C. Beta-galactosidase was present. D. Expression of the lac operon is constitutive whether lacI is functional or not.
C. Beta-galactosidase was present.
Expression of ______ would inhibit X-chromosome inactivation. A. Xic B. Xist C. Tsix D. All of the answers are correct. E. None of the answers are correct.
C. Tsix
Epigenetics may play a role in cancer by A. directly resulting in gene deletions. B. directly inducing inversion mutations. C. causing translocations. D. causing a change in gene expression patterns.
D. causing a change in gene expression patterns.
Acetylation of histones results in A. formation of a closed chromatin structure. B. termination of transcription. C. removal of histones from the histone octamer. D. formation of an open chromatin structure.
D. formation of an open chromatin structure.
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, what type of dominant mutant is this? A. Dominant negative B. Gain of function C. Haploinsufficiency
A. Dominant negative
Riboswitches have been shown to affect regulation of ______. A. transcription and translation B. only RNA splicing C. only transcription D. only translation
A. transcription and translation
In Jacob, Monod, and Pardee's experiment, what would have been the conclusion if all four tubes produced a yellow color when β-ONPG was added? A. LacI provides the binding site for the repressor B. Expression of the lac operon is constitutive whether lacI is functional or not C. LacI encodes a diffusible repressor D. The researcher added too much β-ONPG
B. Expression of the lac operon is constitutive whether lacI is functional or not
Which DNA repair process identifies daughter strands by methylation? A. homologous recombination repair B. mismatch repair C. direct repair D. nucleotide excision repair E. nonhomologous end joining (NHEJ) F. base excision repair
B. mismatch repair
Imagine all the histone H3 molecules in the cell have a mutation that changes their lysine-9 residue to an alanine. Assuming this cell could still live, what would be the result? A) The ability of the cell to form euchromatin would be hindered. B) The ability of the cell to imprint genes would be hindered. C) The ability of the cell to form heterochromatin would be hindered. D) There would little effect because lysine and alanine are similar amino acids.
C) The ability of the cell to form heterochromatin would be hindered. Explanation: Trimethylation of histone H3 of the lysine at the 9th position is important for heterochromatin formation. Mutation of this residue to an alanine would make methylation of this residue impossible and would hinder heterochromatin formation.
The term for the use of information about a person's genotype and other clinical data in order to select a medication is referred to as A) minimalized drug therapy. B) molecular profiling. C) personalized medicine. D) best medical practices.
C) personalized medicine.
Regulation of gene expression may occur at which of the following level? A. transcription B. translation C. posttranslation D. All of the answers are correct.
D. All of the answers are correct.
In the United States, most newborns undergo a test for primary congenital hypothyroidism, a condition where people are unable to produce enough thyroid hormone. On a nationwide basis, this is an example of __________. A. genetic testing B. preimplantation genetic diagnosis C. amniocentesis D. genetic screening
D. genetic screening
What is the difference between genetic testing and genetic screening? A. Genetic testing is concerned more with individuals and genetic screening is concerned with populations. B. Genetic screening is concerned more with individuals and genetic testing is concerned with populations. C. They use different tests and techniques to detect genetic mutations. D. Genetic testing is concerned more with nonlethal syndromes and diseases, and genetic screening is concerned with lethal diseases and syndromes.
A. Genetic testing is concerned more with individuals and genetic screening is concerned with populations.
In cancer cells, one allele of a tumor suppressor gene called p53 is frequently mutated so that the protein is inactive, not produced, or deleted. The other allele usually has a normal sequence and the promoter remains intact, but the gene is not expressed. Sequencing with sodium bisulfite modification of DNA can be used to detect which cytosines are methylated. If cancer cell DNA is sequenced, which of the following results would be expected? A) There will be no differences in the methylation pattern of the promoter of p53 from a cancer cell and a normal cell B) Cytosines in the coding region will have an increased methylation C) Cytosines in or near the promoter region will be methylated D) Cytosines in or near the promoter will not be methylated
C) Cytosines in or near the promoter region will be methylated
What kind of mutation would be expected both within oncogenes and tumor suppressor genes that would result in gain-of-function or loss-of-function, respectively? A. Silent B. Amplifications C. Missense D. Neutral
C. Missense
Allosteric regulation is accomplished by A. a small molecule that fits into a site on the enzyme that is not the active site. B. a small molecule that covalently modifies a site on the enzyme that is not the active site. C. a large protein that blocks an enzyme's active site. D. a small molecule that fits into an enzyme's active site.
A. a small molecule that fits into a site on the enzyme that is not the active site.
If a bacterium is placed in an environment that contains both glucose and lactose, the regulation of the lac operon will allow which nutrient to be processed first? A. glucose B. lactose C. Both will be processed equally. D. Neither will be processed in this environment.
A. glucose
In the following sequence of DNA, the italicized base has been mutated. What type of mutation is this? 5' - G A T C T C C G A A T T - 3' original strand 5' - G A T C T C C C A A T T - 3' mutated strand A) transition B) transversion C) neither
B) transversion (= purine to pyramidine)
Regulatory transcription factors may be regulated by A. lipid modifications. B. phosphorylation. C. binding of carbohydrates. D. sulfation.
B. phosphorylation.
After screening a colony of bacteria for a given gene, you discover 100 mutant colonies out of 3 million total colonies. What is the mutation rate for this gene in the population? A. 1.0 x 10-5 B. 1.0 x 105 C. 3.3 x 10-5 D. 3.0 x 105
C. 3.3 x 10-5
What is an example of a suppressor mutation? A) an intragenic mutation that restores protein structure B) an intergenic mutation that increases the activity of a protein performing the same function as the mutated protein C) an intergenic mutation that alters a transcription factor to activate the expression of a compensating protein D) All of the answers are possible suppressor mutations.
D) All of the answers are possible suppressor mutations.
Which of the following is incorrect regarding the glucocorticoid hormones? A) The homodimer interacts with GRE, activating transcription. B) After interacting with the receptor, they release HSP90. C) The receptors form a homodimer that travels to the nucleus. D)They interact with receptors located in the plasma membrane of the cell.
D)They interact with receptors located in the plasma membrane of the cell.
You are working in a lab where you are studying a disease that is known to be caused by a single nucleotide change, although the effect this change ultimately has on the protein's structure/function is unknown. You have DNA samples from multiple patients that you suspect of having this disease. What is the most efficient way to test the samples for the relevant mutation? A. Karyotyping B. Amniocentesis C. Western blotting D. DNA sequencing
D. DNA sequencing
Regions of chromatin that are more compact are called __________; they are usually found __________ in the nucleus. A. euchromatin; centrally B. euchromatin; at the periphery C. heterochromatin; centrally D. heterochromatin; at the periphery
D. heterochromatin; at the periphery
What are histone variants? A. histone proteins that have slightly different amino acid sequences but are found in nucleosomes throughout the chromosomes B. histone proteins that have been modified by acetylation and phosphorylation C. histone proteins that have been modified by acetylation D. histone proteins that have slightly different amino acid sequences and have specialized functions
D. histone proteins that have slightly different amino acid sequences and have specialized functions
Translational regulatory proteins recognize specific areas of what molecule? A. tRNA B. Ribosome C. rRNA D. mRNA E. None of the answers are correct.
D. mRNA
The Avy allele of the Agouti gene involves the insertion of a transposable element upstream from the normal Agouti promoter. The transposable element carries a promoter that causes the overexpression of the Agouti gene. Mice carrying this allele tend to have coat colors that are more yellow than mice that don't have this transposable element. If pregnant female mice are fed a diet that contains chemicals that inhibit DNA methylation, how would you expect that this diet would affect the coat color of offspring carrying the Avy allele? A) Their fur would be more yellow because the Agouti gene would tend to be over expressed. B) Their fur would be less yellow (darker brown) because the Agouti gene would tend to be over expressed. C) Their fur would be less yellow (darker brown) because the Agouti gene would tend to be under expressed. D) Their fur would be more yellow because the Agouti gene would tend to be under
A) Their fur would be more yellow because the Agouti gene would tend to be over expressed.
A mutation in the lacI gene prevents the gene product from binding allolactose. What will the expression level of the operon be in the absence of lactose? A. No transcription B. Transcription will occur only in the presence of glucose C. Positive regulation D. Constitutively active
A. No transcription
A queen bee is larger than the female worker bees in a hive. The queen develops functional ovaries that allow her to produce up to 2000 eggs a day. What determines which bees become queen bees? A. The larvae raised on a diet of royal jelly B. A single dominant allele of the Queen gene C. The egg that hatches first D. The larvae raised on a diet of pollen and nectar
A. The larvae raised on a diet of royal jelly
The Avy allele of the Agouti gene involves the insertion of a transposable element upstream from the normal Agouti promoter. The transposable element carries a promoter that causes the overexpression of the Agouti gene. Mice carrying this allele tend to have coat colors that are more yellow than mice that don't have this transposable element. If pregnant female mice are fed a diet that contains chemicals that increase DNA methylation, how would you expect that this diet would affect the coat color of offspring carrying the Avy allele? A. Their fur would be less yellow (darker brown) because the Agouti gene would tend to be under expressed. B. Their fur would be more yellow because the Agouti gene would tend to be over expressed. C. Their fur would be more yellow because the Agouti gene would tend to be under expressed. D. Their fur would be less yellow (darker brown) because the Agouti gene would tend to be over
A. Their fur would be less yellow (darker brown) because the Agouti gene would tend to be under expressed.
What would be a set of anticipated results from a "Lederberg" experiment? A. Total number of colonies on a plate: 1500 Total number of resistant colonies on replica plate with T1: 15 B. Total number of colonies on a plate: 1500 Total number of resistant colonies on replica plate with T1: 1500 C. Total number of colonies on a plate: 1500 Total number of resistant colonies on replica plate with T1: 0 D. Total number of colonies on a plate: 500 Total number of resistant colonies on replica plate with T1: 1500
A. Total number of colonies on a plate: 1500 Total number of resistant colonies on replica plate with T1: 15
What are the general ways that tumor suppressors and oncogenes act? A. Tumor suppressors inhibit the cell cycle and oncogenes stimulate the cell cycle. B. Oncogenes inhibit the cell cycle and tumor suppressors stimulate the cell cycle. C. Both tumor suppressors and oncogenes stimulate the cell cycle. D. Both tumor suppressors and oncogenes inhibit the cell cycle.
A. Tumor suppressors inhibit the cell cycle and oncogenes stimulate the cell cycle.
In the analysis of a family, you notice that males are more likely to contract a certain disease, and the daughters of affected males produce 50% of their sons affected with the disease. This disease is displaying which of the following patterns of inheritance? A. X-linked recessive B. autosomal recessive C. autosomal dominant D. None of these choices are correct.
A. X-linked recessive
Four cancer patients are treated with an experimental drug. Patients #2 and #4 have an extremely serious adverse reaction to the drug. Another patient (#5) requests to enter the trial and you do not wish to treat this patient if there is any indication that the new patient will have the same side effect. The haplotypes for the region where the allele that controls this sensitivity has been mapped and the haplotypes for this region for these patients are given below. Should you enter patient #5 into the trial? 1: 1A 2B 3C 4B/1A 2B 3A 4C 2: 1A 2C 3B 4B/1B 2A 3B 4A 3: 1B 2A 3A 4B/1C 2B 3A 4A 4: 1B 2C 3B 4B/1A 2B 3A 4C 5: 1A 2B 3A 4C/1B 2A 3B 4A A. Yes, #5 shares no haplotype combinations with #2 and #4. B. Yes, since there are no shared haplotypes between #2 and #4 these haplotypes are not correlating with the drug sensitivity. C. No, # 5 shares the 1A haplotype with #2 and #4. D. No, # 5 shares the 3B haplotype with
A. Yes, #5 shares no haplotype combinations with #2 and #4.
Genome wide association studies are used __________. A. to identify single nucleotide polymorphisms that are near disease causing genes B. to identify the mutation that causes a disease C. to describe the number of alleles for a specific gene D. to find the total variation that occurs in human genomes
A. to identify single nucleotide polymorphisms that are near disease causing genes
An oncogene form of Ras would have which of the following characteristics? A.decreased GTPase activity B.increased GTPase activity C.decreased exchange of GDP for GTP D.an increased number of copies in the cell
A.decreased GTPase activity
Beechdrops is a parasitic plant that cannot perform photosynthesis but relies on its host the Beech tree. However, beechdrops still retains many if not all of the genes for photosynthesis. Snapdragons and gladiolas are common garden flowers that rely on their ability to perform photosynthesis. If you were to compare the gene sequences for these three plants for ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) a protein necessary for photosynthesis what would you predict? A. The differences between gladiolas and snapdragons would most likely be missense mutations while those in beechdrops may be silent or missense B. The differences between gladiolas and snapdragons would most likely be silent mutations while those in beechdrops may be silent or missense C. Since these three plants are not highly related the sequences for RuBisCO would be very different between them D. The differences between gladiolas and
B. The differences between gladiolas and snapdragons would most likely be silent mutations while those in beechdrops may be silent or missense
If the individuals in the picture above had a child, that child could have which haplotype listed (assuming no crossing over)? A.1A2A3A4A; 1B2B3A4B B.1A2A3A4A; 1C2C3C4A C.1A2B3B4C; 1C2C3C4A D.1A2B3C4A; 1C2C3B4C
B.1A2A3A4A; 1C2C3C4A
Which of the following statements are correct? A) Changes in gene expression based on environmental conditions are not considered normal while developmental changes are. B) Environmental epigenetic gene regulation is typically reversible while developmental epigenetic gene regulation is typically not reversible. C) Environmental epigenetic changes can vary due to the exposure of the organism to different environmental conditions, while those programmed during development are the result of stimuli generated by the organism itself. D)Environmental epigenetic gene regulation only occurs in reptiles and insects, while developmental epigenetic regulation occurs in all animals.
C) Environmental epigenetic changes can vary due to the exposure of the organism to different environmental conditions, while those programmed during development are the result of stimuli generated by the organism itself.
Chromatin remodeling complexes alter nucleosomes, this occurs when A) remodeling proteins bind to TFIID to promote or inhibit nucleosome formation. B) complexes of ATP-dependent protein degrade histones and release the DNA from nucleosomes. C) complexes of ATP-dependent proteins may reposition, evict, or change nucleosome composition. D) remodeling proteins increase the supercoiling of the DNA, which can inhibit nucleosome formation.
C) complexes of ATP-dependent proteins may reposition, evict, or change nucleosome composition.
What are some types of the molecular changes that underlie epigenetic gene regulation? A. DNA methylation and depurination of cytosine residues B. depurination and chromatin remodeling. C. DNA methylation and chromatin remodeling D. depurination of cytosine and thymidine residues
C. DNA methylation and chromatin remodeling
What is a major difference between the general and regulatory transcription factors? A. General transcription factors act as heterodimers while regulatory transcription factors act as monomers. B. General transcription factors only regulate the housekeeping genes while regulatory transcription factors control all of the other genes. C. General transcription factors are essential for any transcription for all genes while regulatory transcription factors regulate transcription of specific genes. D. General transcription factors regulate basal genes while regulatory transcription factors control all of the other genes.
C. General transcription factors are essential for any transcription for all genes while regulatory transcription factors regulate transcription of specific genes.
Which of the following is correct regarding the rate of mutation? A. Mutation rates are consistent across species. B. Mutation rates are constant. C. Rates of mutation per cell generation typically range from 10−5 to 10−9. D. Mutation rates are not influenced by environmental conditions.
C. Rates of mutation per cell generation typically range from 10−5 to 10−9.
A deletion in an operon removes the terminator. How will that affect the transcript that is produced from the operon? A. The transcript will be produced and normal in length B. The transcript will be produced, but will contain a deletion C. The transcript will be produced, but longer than normal D. The transcript will not be produced E. The transcript will be produced, but shorter than normal
C. The transcript will be produced, but longer than normal
The conversion of cytosine to uracil in DNA is an example of _____. A. depurination B. tautomeric shifts C. deamination D. None of the answers are correct.
C. deamination
What effect will a mutation in IRP that prevents it from binding to iron have on an individual? A) Ferritin will not be made, so iron intake must be maximized. B) There will be excess ferritin, so iron intake must be lowered. C) Transferrin will not be made, so iron intake must be maximized. D) There will be excess transferrin, so iron intake must be lowered.
D) There will be excess transferrin, so iron intake must be lowered. Explanation The iron regulatory protein (IRP) binds to the IRE of the ferritin mRNA, preventing translation. When iron binds to the IRP, the IRP is released from the IRE and translation of ferritin proceeds. At the transferrin receptor mRNA, the IRP enhances the stability of the mRNA. When IRP binds iron, the IRP is released from the transferrin receptor mRNA, and the mRNA is degraded. At the ferritin mRNA, inability of the IRP to bind iron would mean the IRP would remain bound to the ferritin mRNA and ferritin would not be made, which would mean there would not be ferritin to store excess iron. In the case of the transferrin receptor mRNA, this mRNA would be extra stable because the IRP would remain bound to the mRNA. This would mean excess transferrin receptor would be made, which would lead to more iron being imported. This would especially be a problem in the absence of ferritin. Therefore iron intake would need to be lowered.
Regulatory transcription factors may influence gene expression in which of the following ways? A) by directly interacting with TFIII to inhibit its binding to the core promoter B) influencing the ability of the RNA polymerase to perform elongation C) directly recruiting RNA polymerase to the promoter without interacting with any other proteins D) recruiting proteins to the promoter that enhance chromatin compaction
D) recruiting proteins to the promoter that enhance chromatin compaction
How does position effect influence gene expression? A. The movement of the genetic material on the chromosome by inversions or translocations may place a coding sequence near a new regulatory region, thus activating the expression of the gene. B. The movement of the gene may place it into a region that is highly condensed. C. The movement of a gene may remove it from its normal promoter, thus silencing the gene. D. All of the answers are correct.
D. All of the answers are correct.
What gene(s) is/are encoded in the Xic? A. Xce B. Xist C. Tsix D. Both the Tsix and Xist are genes are in the Xic region
D. Both the Tsix and Xist are genes are in the Xic region
Most trinucleotide repeat expansion repeats involve expansion of which of the following? A. GAA B. any codon containing three of the same bases C. ATG D. CAG
D. CAG
An example of personalized medicine would be A. performing an appendectomy on a patient with appendicitis. B. treatment of diabetics with synthetic instead of natural insulin. C. treatment of an infection based on the drug resistance of the bacterium. D. determining the CYP2C9 alleles present to help set the patient's coumarin dose.
D. determining the CYP2C9 alleles present to help set the patient's coumarin dose.
You are a doctor tasked with diagnosing a patient that comes to you with mental impairment. Upon performing genetic tests, you find he has approximately 300 repeats of GCC in one of his genes. His father and grandfather had similar mental impairment but were never diagnosed with a condition prior to their death. His grandmother, mother, and sisters are unaffected. What disease do you predict that this patient has? A.SBMA B.FRAXA C.HD D.FRAXE E.SCA1
D.FRAXE
Which of the following is typically associated with an autosomal recessive pattern of inheritance? A.an affected individual with one affected parent will have 50% of its offspring affected B.an affected offspring has one or more affected parents C.two affected heterozygous individuals will have 25% of their offspring unaffected D.an affected offspring has two unaffected parents
D.an affected offspring has two unaffected parents
Tamoxifen is a medication used for treating cancer. Many women were found to have resistance to this drug, and research showed that women with a mutation in their CYP2D6 gene could not break down Tamoxifen. Therefore Tamoxifen was not a useful treatment for their cancer. Women can now be screened for this mutation, allowing clinicians to use a therapy that is effective for each woman. This type of treatment is an example of __________. A.haplotype association studies B.loss of heterozygosity C.karyotyping D.personalized medicine
D.personalized medicine
