GENETICS EXAM 1-4 (COMBINED) UH LIN/DAANE
DNA synthesis (addition of nucleotides) during replication proceeds in which direction? A) 5' to 3' B) 3' to 5' C) Either direction D) Depends on which strand E) Start to stop codon
A) 5' to 3'
What is the probability that an offspring will have an ssRR genotype from a cross of two SsRr individuals? A) 6.25% B) 25% C) 3.12% D) 12.5%
A) 6.25%
You are studying a new species of plant similar to Mendel's pea plants. You are specifically interested in two genes that are located on two different chromosomes. In this plant, the gene for height has two alleles, T (tall) and t (short). The gene for leaf color has two alleles P (purple) and p (pink). What meiotic products do you expect from diploid cells that are homozygous for the tall allele and heterozygous for the leaf color alleles? A) An equal number of TP and Tp gametes B) An equal number of TP and tp gametes C) 2 TP gametes for every 1 Tp gamete D) An equal number of Tp, tP, tp, and TP gametes
A) An equal number of TP and Tp gametes
What observations were crucial in allowing Watson and Crick to propose the double helix structure of DNA? A) Chargraff's rule of the relative frequency of different nucleotides and Franklin's X-ray diffraction of a DNA molecule. B) Griffiths' observation of a transforming factor. C) Hershey and Chase's demonstration of DNA as a genetic material. D) The determination of the genetic code by Nirenberg and Khorana. E) All of the above.
A) Chargraff's rule of the relative frequency of different nucleotides and Franklin's X-ray diffraction of a DNA molecule.
What type of molecule is the lac operator? A) DNA B) RNA C) Protein D) Sugar E) Lipid
A) DNA
The terms genome, proteome, and transcriptome refer to the complete or comprehensive information contained in which of the corresponding molecules (in order they are listed)? A) DNA, protein, RNA B) DNA, RNA, protein C) RNA, DNA, protein D) RNA, protein, DNA E) protein, DNA, RNA
A) DNA, protein, RNA
In a dihybrid cross of two heterozygous individuals, you expect a 9:3:3:1 phenotypic ratio in the offspring, but observe a ratio of 9:7. What is the most likely explanation? A) Epistatic interaction of the two genes B) Simple Mendelian inheritance C) Codominance D) It is a sex-limited trait E) Incomplete penetrance
A) Epistatic interaction of the two genes
In cancer cells, the number of transcripts mapped to Gene X is 47; in normal cells from the same tissue, the number of Gene X transcripts is 128. How would you interpret these RNA-seq results? A) Gene X is expressed at lower levels in cancer cells. B) Gene X is expressed at higher levels in cancer cells. C) Gene X expression cannot be determined based on the data presented. D) Gene X encodes a non-coding RNA. E) Two of the above
A) Gene X is expressed at lower levels in cancer cells.
Acetylated histones are associated with which effect on gene transcription? A) Increase in transcription B) Decrease in transcription C) Increase in transcription termination D) Decrease in transcription termination E) Increase in splicing
A) Increase in transcription
What is the approximate cost of sequencing an individual human genome today using next-generation sequencing technology? A) Less than $1000 B) $3 billion C) $1 million D) $100,000 E) $25,000
A) Less than $1000
For organisms which use photolyase to repair thymine dimers, what is the source of energy used to break the bonds which form the dimers? A) Light B) ATP C) GTP D) cAMP E) Allolactose
A) Light
Which of the following statements correctly describes oncogenes and tumor suppressor genes in cancers? A) Oncogenes are overexpressed or hyperactive whereas tumor suppressor genes are silenced (not expressed) or have loss-of-function mutations. B) Tumor suppressor genes are overexpressed or hyperactive whereas oncogenes are silenced (not expressed) or have loss-of-function mutations. C) Both oncogenes and tumor suppressor genes are overexpressed or hyperactive. D) Both oncogenes and tumor suppressor genes are suppressed or have loss-of-function mutations. E) All of the above.
A) Oncogenes are overexpressed or hyperactive whereas tumor suppressor genes are silenced (not expressed) or have loss-of-function mutations.
Which component of the telomerase complex provides the template to extend the overhang left by the removal of the RNA primer? A) RNA B) 5' end of the Okazaki fragment C) 3' end of Okazaki fragment D) 3' end of the leading strand E) 3' end of the lagging strand
A) RNA
According to the RNA World theory on the origin of the molecular components and mechanisms of life, ... A) RNA contained genetic information and catalyzed chemical reactions in protobionts. B) RNA was the only molecule when the first cells formed. C) RNA was the earliest molecule found on the planet. D) First proteins were made with RNA nucleotides instead of amino acids. E) RNA was the energy source used by protobionts.
A) RNA contained genetic information and catalyzed chemical reactions in protobionts.
Regulation of glucocorticoid receptor and its transcriptional activity by the steroid glucocorticoid hormone is an example of which type of transcription factor regulatory mechanisms in eukaryotes? A) Small molecule effectors B) Protein-protein interactions C) Covalent modification D) Negative feedback E) Attenuation
A) Small molecule effectors
What is the advantage of using nuclei of blood cells collected from the umbilical cord of a baby versus those from adult skin cells for reproductive cloning? A) Telomeres are longer in cord blood cells. B) Telomeres are shorter in cord blood cells. C) The histones are acetylated in cord blood cells. D) The histones are deacetylated in cord blood cells. E) None. There is no advantage to using nuclei from one cell type as compared to others.
A) Telomeres are longer in cord blood cells.
The nucleotide sequence in the resulting RNA transcript is complementary to the sequence in which strand of the gene? A) Template strand B) Coding strand C) Sense strand D) Leading strand E) Lagging strand
A) Template strand
Recombinant bacteria have been engineered to produce human insulin. Which of the following is the strategy used to do so? A) The A and B chains of insulin are expressed separately in bacteria and then purified and combined to allow proper folding and formation of disulfide bonds to form active insulin. B) Bacteria are injected with human insulin, which they then copy and mass produce. C) Special nutrients (sugars) are used to culture the bacteria, and they naturally produce insulin to counteract the increase in sugar levels. D) Bacteria are fused with human pancreatic β cells which produce insulin. This will allow the recombinant bacteria to produce insulin, like the β cells. E) Nice try Dr. Lin. Bacteria can't make human proteins.
A) The A and B chains of insulin are expressed separately in bacteria and then purified and combined to allow proper folding and formation of disulfide bonds to form active insulin.
In a chi-square test to determine if two genes are linked or assorting independently, what is the default (null) hypothesis that is tested? A) The genes are assorting independently. B) The distance between the genes is very small. C) The genes are located on the sex chromosomes. D) The genes are linked to one another. E) No crossing over occurs.
A) The genes are assorting independently.
What would be the consequence if the telomerase gene has been mutated in an eukaryotic cell and is no longer functional? A) The telomeres will shorten in subsequent generations. B) The telomeres will lengthen in subsequent generations. C) Leading strand synthesis will be blocked. D) Lagging strand synthesis will be blocked. E) Two of the above
A) The telomeres will shorten in subsequent generations.
What is a possible consequence of mutation within the enhancer region of a eukaryotic gene if the activator protein is no longer able to bind? A) There is a decrease in transcription. B) There is an increase in transcription. C) A different amino acid will be added to the resulting protein. D) A codon for an amino acid in the gene will be converted into a stop codon. E) The reading frame will be shifted in the resulting mRNA during translation.
A) There is a decrease in transcription.
Transcripts are categorized as non-coding RNAs based on which of the following characteristics? A) They do not code for proteins but rather function as RNAs. B) They are not encoded by a DNA sequence, hence the name. C) They use a different genetic code and codons than mRNAs. D) They interfere with the interaction between codons and tRNA anticodons. E) All of the above.
A) They do not code for proteins but rather function as RNAs.
Mutations can have both positive and negative consequences for gene function and the evolution of organisms. True or False? A) True B) False
A) True
You are working with fruit flies, but you forgot to write down the parents of your cross. You count the progeny, and find you have 40 red-eyed males, 80 red-eyed females, and 40 white-eyed males. White eyes (w) are recessive to red (w+). Assuming that all genotypes from this cross should have equal survival rates, what are the genotypes of the parent flies? A) X^w+ Y and X^w+ X^w B) X^w+ Y and X^w X^w C) X^w Y and X^w+ X^w D) X^w Y and X^w+ X^w+x
A) X^w+ Y and X^w+ X^w
The physical structure that is formed when two chromatids cross over is called a(n) _______. A) chiasma B) karyotype C) bivalent D) synaptonemal complex
A) chiasma
A transgenic animal, by definition, has been engineered to... A) express a gene from another species. B) convert one gene to another. C) increase transcription of its genes. D) decrease transcription of its genes. E) be immune to infection by bacteriophages.
A) express a gene from another species.
You are working in an Arabidopsis lab. You identify a mutant strain of plants that grows curly leaves. You now need to determine what gene is mutated in these mutant plants. This is an example of __________. A) forward genetics B) reverse genetics C) gene knockout D) heterochronic mutations
A) forward genetics
In maternal effect, the __________ of the mother determines the __________ of the offspring. A) genotype; phenotype B) phenotype; genotype C) rRNA; tRNA D) imprinting; genotype E) X-inactivation; genotype
A) genotype; phenotype
The term for the probability that a gene will be altered by a new mutation is __________. A) mutation rate B) evolution rate C) microevolution rate D) selection rate
A) mutation rate
Two genes that are located on the same chromosome are said to be _________ A) physically linked B) parental-like C) nonparental-like D) recombinant
A) physically linked
Morphogens, induction, and cell adhesion provide __________ to a developing organism. A) positional information B) maternal effect genes C) homeodomains D) lineage tracing
A) positional information
In bacterial inducible gene regulation, a small molecule inducer binds to a repressor and... A) prevents it from binding to DNA. B) helps it bind to DNA. C) inhibits gene transcription. D) prevents RNA polymerase from binding to the promoter. E) increases its binding to cAMP.
A) prevents it from binding to DNA.
Using the clone-by-clone approach to obtain the first draft of the human genome sequence would have... A) taken longer to complete the sequencing of the genome. B) taken less time to complete the sequencing of the genome. C) been impossible since the technology was not mature enough. D) no effect on the speed of sequencing the human genome. E) Two of the above
A) taken longer to complete the sequencing of the genome.
How many Barr bodies would an individual with a XXY genotype possess? A) 0 B) 1 C) 2 D) 3 E) None of the above.
B) 1
In a given population of Drosophila, curly wings (c) is recessive to the wild-type condition of straight wings (c+). You isolate a population of 35 curly winged flies, 70 flies that are heterozygous for straight wings and 45 that are homozygous for straight wings. What is the frequency of alleles in this population? A) 35% c; 45% c+ B) 46.7% c; 53.3% c+ C) 50% c; 50% c+ D) 55% c; 45% c+ E) The frequencies cannot be calculated from the provided information.
B) 46.7% c; 53.3% c+
In a dihybrid cross using Mendelian inheritance, if both parents are heterozygous for both traits, what will be the phenotypic ratio of their offspring? A) 3:1 B) 9:3:3:1 C) 1:1 D) 1:2:1
B) 9:3:3:1
How does haploinsufficiency explain dominance of an allele that codes for a non-functional protein over an allele that codes for a functional protein? A) A single functional copy of the gene produces sufficient gene product for normal biological function B) A single functional copy of the gene produces insufficient gene product for normal biological function C) The null allele produces a product that does not interfere with proper function of the normal allele product D) The null allele rapidly mutates to reacquire normal functionality
B) A single functional copy of the gene produces insufficient gene product for normal biological function
What form of cladogenesis occurs due to geographic separation dividing a population? A) Parapatric speciation B) Allopatric speciation C) Sympatric speciation D) Adaptive radiation
B) Allopatric speciation
A couple both have a particular genetic condition. They have eight children (4 male and 4 female) and only two of them (1 male and 1 female) do not have the condition. What would you conclude about the possible mode of inheritance? A) Autosomal recessive B) Autosomal dominant C) X-linked recessive D) X-linked dominant E) Epigenetic mechanisms
B) Autosomal dominant
How would you experimentally demonstrate that Group I and Group II self-splicing introns do not require proteins? A) By adding DNase B) By adding Protease C) By adding RNase D) By adding extra proteins E) By adding extra RNA
B) By adding Protease
RNA sequencing or RNA-seq is used to determine which of the following? A) Damages to the genome in response to mutagens B) Changes in transcriptome under different conditions C) Different aspects of the proteome, including chemical modifications D) Protein interactomes in specific pathways E) None of the above.
B) Changes in transcriptome under different conditions
(HAS AN IMAGE) You are a researcher examining the expression pattern of a wobbly fly phenotype. You have flies that fly straight and those having a wobble flight. When you cross a straight flying strain with a strain showing a wobble flight, all the F1 flies fly straight. In the F2 generation, you get 762 straight flying flies and 238 wobbly flies. Your null hypothesis is that one gene controls flight patterns and that straight is dominant to wobbly. Use chi square analysis to test your hypothesis. What is your chi square number? Do you reject or accept the null hypothesis? Use the table listed below to help answer the question. A) Chi square = 0.768; reject B) Chi square = 0.768; accept C) Chi square = 0.192; reject D) Chi square = 0.192; accept
B) Chi square = 0.768; accept
RNA primers used in DNA replication in bacteria are removed by... A) DNA polymerase III 3' to 5' exonuclease activity B) DNA polymerase I 5' to 3' exonuclease activity C) RNase which digests the primers. D) Helicase which separates the primers from the DNA strand E) Primase and its 3' to 5' exonuclease activity
B) DNA polymerase I 5' to 3' exonuclease activity
What is the natural function of the CRISPR-Cas system in bacteria? A) Regulate mRNA stability B) Defend against bacteriophage infection C) Induce the expression of genes involved in sugar metabolism D) Limit DNA damage and activate repair E) Activate transcription of non-coding RNAs
B) Defend against bacteriophage infection
In which type of inheritance does a change in phenotype of the offspring not rely on a change in the DNA sequence? A) Maternal inheritance B) Epigenetic inheritance C) Paternal inheritance D) Maternal effect E) Sex-linked inheritance
B) Epigenetic inheritance
It is possible for mutations to have no effect on the amino acid sequences of resulting proteins. These are known as nonsense mutations. True or False? A) True B) False
B) False
The formula p2 + 2pq + q2 = 1 is associated with which of the following? A) Calculations of heterozygosity B) Hardy-Weinberg equilibrium C) Calculations of recombination frequencies D) Degrees of freedom
B) Hardy-Weinberg equilibrium
Which of the following statements is true regarding the inheritance pattern of genetic conditions or diseases? A) Fraternal twins share the disease more frequently than identical twins. B) Identical twins share the disease more frequently than fraternal twins. C) There is no difference in the frequency of condition or disease in fraternal twins as compared to identical twins. D) The inheritance pattern is unpredictable, even in twins. E) None of the above
B) Identical twins share the disease more frequently than fraternal twins.
What is the role of the Mediator protein in eukaryotic gene regulation? A) It mediates the binding of the spliceosome. B) It mediates the interaction between transcription factors bound to regulatory sequences and the general transcription factors and RNA polymerase in the promoter region. C) It mediates the synthesis of RNA in 5' to 3' direction. D) It mediates the binding of mRNA to the ribosome to initiate translation by placing the initiator tRNA in the P site with the start codon. E) None of the above
B) It mediates the interaction between transcription factors bound to regulatory sequences and the general transcription factors and RNA polymerase in the promoter region.
(HAS AN IMAGE) The wild-type mRNA has the following sequence at the beginning of the coding region (the codons are shown, including the start codon): AUG GCC GGA CUU UUU GCC Which of the following is the resulting amino acid sequence if an A is inserted between the first and the second codons (use the Genetic Code table included in the exam)? A) Met, Ala, Gly, Leu, Phe, Ala B) Met, Ser, Arg, Thr, Phe, Cys C) Met, Gly, Ala, Phe, Cys, Pro D) Met, Thr, Ala, Gly, Leu, Lys E) Can't determine using the information given.
B) Met, Ser, Arg, Thr, Phe, Cys
Where is extranuclear DNA located in mammalian cells? A) Endoplasmic reticulum B) Mitochondria C) Ribosome D) Plasma membrane E) Lysosome
B) Mitochondria
In a mapping experiment with three linked genes, which phenotype should occur most often in the F2 offspring? A) Phenotypes of individuals with single crossover events. B) Parental phenotypes. C) Phenotypes of individuals with double crossover events. D) All of the phenotypes should occur equally in the F2 generation.
B) Parental phenotypes.
Adjacent nucleotides on the same strand of a DNA molecule are held together by what kind of bonds? A) Peptide bonds B) Phosphodiester bonds C) Hydrogen bonds D) Deoxyribophosphodiester bonds E) Ionic interactions
B) Phosphodiester bonds
The production of sterile offspring in a hybrid mating event between two species an example of a _________. A) Prezygotic isolation mechanism B) Postzygotic isolation mechanism C) Hybrid zone D) Parapatric speciation
B) Postzygotic isolation mechanism
Which of the following indicates the correct order of these events? A) Metaphase - Prometaphase - Prophase - Anaphase - Telophase B) Prophase - Prometaphase - Metaphase - Anaphase - Telophase C) Telophase - Prometaphase - Prophase - Metaphase - Anaphase D) Anaphase - Telophase - Prophase - Prometaphase - Metaphase
B) Prophase - Prometaphase - Metaphase - Anaphase - Telophase
Bacterial promoters contain -35 and -10 consensus sequences. What is the consequence if the -35 sequence has been mutated and no longer recognized by trans-acting factors? A) RNA polymerase core enzyme will not bind DNA. B) Sigma factor will not bind and the -10 sequence will not be "open" to initiate transcription. C) Sigma factor will bind and the -10 sequence will be "open" to initiate transcription. D) Transcription of the affected gene will increase. E) Two of the above
B) Sigma factor will not bind and the -10 sequence will not be "open" to initiate transcription.
Which part of the CRISPR locus in the bacterial chromosome contains the "collected" bacteriophage sequences? A) Repeats B) Spacers C) Cas1 D) tracr E) Cas9
B) Spacers
(HAS AN IMAGE) An important enzymatic protein isolated from Drosophila melanogaster was shown to have the following initial sequence of amino acids: Wildtype: Lys - Ser - Pro - Trp - His - . . . . . . Following exposure to x-rays, a series of mutant flies developed, each of which lacked normal activity for this enzyme. One of the mutant enzymes was isolated and displayed the following amino acid sequence: Mutant: Lys - Arg - Pro - Trp - His - . . . . . . What is the likely mutation which led to the observed amino acid sequence for the mutant (use the Genetic Code table included in the exam)? A) A base was deleted between the second and third codons. B) Substitution of the third base in the second codon. C) Nonsense mutation was introduced. D) Substitution of the second base in the second codon. E) An extra base was inserted between the second and third codons.
B) Substitution of the third base in the second codon.
What happened when Celera Corporation (Craig Venter) entered the race to sequence the human genome? A) It slowed down the effort due to the competition with the public Human Genome Project and delayed the completion of the first draft by years. B) The competition sped up the effort by the public Human Genome Project, leading to an earlier completion of the first draft. C) It had no impact on the sequencing of the human genome since it's privately funded. D) It caused the sequencing of the human genome to stop completely due to ethical concerns about commercialization of the genome sequence data. E) The impact remains to be seen since the sequencing is still ongoing.
B) The competition sped up the effort by the public Human Genome Project, leading to an earlier completion of the first draft.
DNA ligase is commonly found on which strand during replication? A) The leading strand B) The lagging strand C) The sense strand D) Both A and B E) None of the above
B) The lagging strand
Which of the following strands will require constant priming during DNA replication? A) The leading strand B) The lagging strand C) The sense strand D) Both A and B E) None of the above
B) The lagging strand
(HAS AN IMAGE) An important enzymatic protein isolated from Drosophila melanogaster was shown to have the following initial sequence of amino acids: Wildtype: Lys - Ser - Pro - Trp - His - . . . . . . Following exposure to x-rays, a series of mutant flies developed, each of which lacked normal activity for this enzyme. One of the mutant enzymes was isolated and displayed the following amino acid sequence: Mutant: Lys - Arg - Pro - Trp - His - . . . . . . What is the likely mutation which led to the observed amino acid sequence for the mutant (use the Genetic Code table included in the exam)? A) Transition of the third base in the second codon. B) Transversion of the third base in the second codon. C) Insertion of the third base in the second codon. D) Deletion of the third base in the second codon. E) Methylation of the third base in the second codon.
B) Transversion of the third base in the second codon.
The coat color of calico cats is a result of which of the following? A) Maternal inheritance B) X-inactivation C) Imprinting D) Extranuclear inheritance E) Paternal inheritance
B) X-inactivation
The prevalence of the allele for sickle cell anemia in some populations is an example of __________. A) heterogeneous environments B) balancing selection C) inverted selection D) non-Darwinian selection E) nonrandom mating
B) balancing selection
The histone code refers to... A) how specific histones code for codons. B) combinations of different histone modifications and their consequences on chromatin structure. C) the code that determines which histone is expressed. D) the order in which histones are assembled to form nucleosomes. E) None of the above
B) combinations of different histone modifications and their consequences on chromatin structure.
Crossing over is more likely to occur between genes that are __________ on a chromosome A) close together B) far apart
B) far apart
The genetic composition of an individual is called its _____________ A) none of these choices are correct B) genotype C) phenotype D) dominance E) hybrid
B) genotype
You identify a new gene that you believe is important in regulating eye development in Drosophila. What approach could you use to identify where the RNA for that gene is expressed in the embryo? A) horizontal gene transfer B) in situ hybridization C) immunostaining D) forward genetics
B) in situ hybridization
A heterozygote possesses a phenotype that is intermediate between the homozygous dominant and homozygous recessive phenotypes. This is most likely an example of ________. A) lethal alleles B) incomplete dominance C) sex-influenced inheritance D) gene dosage
B) incomplete dominance
A karyotype is a(n) _____. A) organelle of eukaryotic cells. B) organized representation of the chromosomes within a cell. C) stage of prophase I in meiosis. D) protein complex bound to the centromere of an individual chromosome. E) division of the cytoplasmic material following mitosis.
B) organized representation of the chromosomes within a cell.
Homologous genes that are found in different species are called __________. A) paralogs B) orthologs C) gene families D) clades
B) orthologs
A group of individuals from the same species that occupy the same region and can interbreed with one another is the definition of a ________. A) species B) population C) race D) community E) kingdom
B) population
All incoming tRNAs bind to the A site of the ribosome with the exception of ... A) the terminator tRNA. B) the initiator tRNA. C) the arginine-tRNA. D) all of the above. E) none of the above. All tRNAs enter at the A site.
B) the initiator tRNA.
RNA nucleotides differ from DNA nucleotides in that RNA nucleotides have a.... A) -OH group at the 5' carbon B) -OH group at the 3' carbon C) -OH group at the 2' carbon D) -H group at the 2' carbon E) -OH group at the 4' carbon
C) -OH group at the 2' carbon
(HAS AN IMAGE) Wild-type Drosophila have red eyes, but it is possible to isolate mutants that have different eye colors. The chart below summarizes the results of crosses between pure-breeding flies with different eye colors + = wildtype phenotype (= red eyes) - = non-wildtype phenotype Based on the chart, how many eye-color mutants have mutations in the SAME gene as the Garnet mutant? (Assume that all mutant alleles are recessive.) A) 2 B) 3 C) 0 D) 6
C) 0
If the genetic code is made of two-base codons, how many different amino acids at most can be encoded by such a code? (Hint: a one-base codon can code for only 4 different amino acids. Also don't worry about start and stop codons, for now.) A) 64 B) 4 C) 16 D) 20 E) 8
C) 16
A couple knows that a particular genetic disease has affected members of their extended families. They are not affected by the disease but were both tested prior to having children and found out that they are both heterozygous for the disease allele. What percentage of their offsprings are likely to have the genetic disease if they choose to have children? A) 100% B) 50% C) 25% D) 0% E) Cannot determine based on the information
C) 25%
The common goldfish Carassius auratus has 100 chromosomes and is tetraploid. The goldfish therefore has __________ sets of chromosomes containing __________ chromosomes each A) 1; 100 B) 4; 100 C) 4; 25 D) 2; 50
C) 4; 25
An individual with type A blood and an individual with type B blood mate and have offspring. What blood type is not possible in their offspring? A) Type O blood B) Type AB blood C) All blood types are possible D) Type B blood E) Type A blood
C) All blood types are possible
Please order the following types of tumors based on increasing number of accumulated mutations (from least to most number of mutations): Malignant, Metastatic, Benign A) Metastatic, Malignant, Benign B) Malignant, Metastatic, Benign C) Benign, Malignant, Metastatic D) Metastatic, Benign, Malignant E) Benign, Metastatic, Malignant
C) Benign, Malignant, Metastatic
What is the function of the Cas9 protein in the CRISPR-Cas system? A) Cut the CRISPR RNA B) Cut the TRACR RNA C) Cut the target DNA D) Bind mediator proteins to enhance transcription E) Stabilize RNA polymerase binding to promoters
C) Cut the target DNA
Which of the following types of selection favors one extreme of a phenotypic distribution? A) Disruptive selection B) Stabilizing selection C) Directional selection D) Balancing selection
C) Directional selection
You plan to heat a collection of DNA samples with known sequences to separate the two strands. Which of the following samples will require the most amount of heat to separate? A) AAAAATTTTTTT B) ATTAGCTTGGTC C) GGGCTTTTCCTA D) CCTATATTAGGG E) GGCCGAAATTTT
C) GGGCTTTTCCTA
Imagine that an RNA polymerase is transcribing a segment of DNA that contains the sequence below. If the polymerase transcribes this sequence from left to right, what will the sequence of the RNA be? 5'-GTAACGGATG-3' 3'-CATTGCCTAC-5' A) GTAACGGATG B) CATTGCCTAC C) GUAACGGAUG D) CAUUGCCUAC E) GUAGGCAAUG
C) GUAACGGAUG
If a snail that has a right hand twist and is DD is mated to a snail that has a left hand twist and is dd what is the expected ratio of progeny? A) 3 left hand to 1 right hand B) 3 right hand to 1 left hand C) It depends on which snail is female and which is male. D) 1 left hand to 1 right hand E) 1 right hand to 1 left hand
C) It depends on which snail is female and which is male.
How does glucose play a role in regulating the lac operon? A) High glucose increases intracellular cAMP levels and activates CAP. B) High glucose decreases intracellular cAMP levels and activates CAP. C) Low glucose increases intracellular cAMP levels and activates CAP. D) Low glucose decreases intracellular cAMP levels and activates CAP. E) None of the above.
C) Low glucose increases intracellular cAMP levels and activates CAP.
What type of molecule is the lac repressor? A) DNA B) RNA C) Protein D) Sugar E) Lipid
C) Protein
In the Hershey-Chase blender experiment, if 35S was detected inside the bacteria and next generation of phages, we would have to conclude... A) DNA is the genetic material B) RNA is the genetic material C) Protein is the genetic material D) Sulfur is the genetic material E) Carbohydrate is the genetic material
C) Protein is the genetic material
If, hypothetically, RNA is the genetic material in the pneumococcal bacteria used in Avery, McLeod, and McCarty's transformation experiment, which of the following would be true about their results: A) DNase treatment would abolish transformation activity of the S bacteria extract. B) RNase treatment would enhance the transformation activity of the S bacteria extract. C) RNase treatment would abolish the transformation activity of the S bacteria extract. D) Protease treatment would abolish the transformation activity of the S bacteria extract. E) Protease treatment would enhance the transformation activity of the S bacteria extract.
C) RNase treatment would abolish the transformation activity of the S bacteria extract.
A homeotic mutation results in which of the following? A) Incorrect formation of the body axes B) Replacement of segments with parasegments C) Replacing one body part with another D) Apotosis
C) Replacing one body part with another
In peas, the round allele (R) is dominant to the wrinkled allele (r). A plant with roundpeas is crossed to a plant with wrinkled peas, and half of the resulting plants have round peas. What are the most likely genotypes of the parents in this cross? A) RR × rr B) RR × Rr C) Rr × rr D) Rr × Rr E) rr × rr
C) Rr × rr
One of the ways to computationally (bioinformatics) determine if a genome sequence codes for a protein-coding gene is to "translate" the sequence into all possible amino acid sequences and then compare the amino acid sequences to those of known proteins in the database. For any given region of the genome, how many different reading frames and resulting amino acid sequences would the algorithm use and produce to perform the analysis? (Hint: How many strands in a DNA molecule?) A) One, only one is used by the ribosome B) Three C) Six D) Twelve E) Sixty-four
C) Six
In this equation p2 + 2pq + q2 = 1, what does the term 2pq represent? A) The genotype frequency of homozygous recessive individuals B) The genotype frequency of homozygous dominant individuals C) The genotype frequency of heterozygous individuals D) The sum of the phenotype frequencies in the population
C) The genotype frequency of heterozygous individuals
In reproductive cloning of animals, what is transferred from the donor animal to the enucleated egg? A) The nucleus of its sperm B) The nucleus from its egg C) The nucleus from a diploid cell D) The mitochondria from a diploid cell E) The X chromosome from a diploid cell
C) The nucleus from a diploid cell
Scientists suspect that a tumor suppressor gene has been "mutated" in a particular patient. When they examined the tumor following surgery, they found that the coding sequence has not been altered but the gene is not expressed (transcript or protein) in the tumors. Which is the likely mechanism by which the tumor suppressor gene was silenced? A) There is a silent mutation in the gene which could not be detected. B) There is a missense mutation in the gene which prevented its expression. C) There is a mutation in the gene promoter which prevented its expression. D) There is a mutation in a nearby non-coding RNA gene. E) Two of the above.
C) There is a mutation in the gene promoter which prevented its expression.
Alkylation of DNA can affect DNA replication and transcription. How do cells repair such damages? A) These damages cannot be repaired and the cell dies. B) These damages are also repaired by photolyase. C) These damages can be directly reversed by alkyltransferase enzymes which remove the alkyl group. D) Nothing is done to repair this type of damage. Alkylated DNA has no effect on replication or transcription. E) Nothing is done to repair this type of damage since they help give rise to new genetic variation and alleles, and this is actually beneficial to the cell.
C) These damages can be directly reversed by alkyltransferase enzymes which remove the alkyl group.
Rho-dependent and Rho-independent transcriptional termination have which of the following in common? A) They both involve rut sites. B) They both involve release factors. C) They both use stem-loop structures formed in the RNA to stop or pause transcription. D) They both do not require proteins for termination. E) They both depend on the 3' to 5'exonuclease activity of RNA polymerase.
C) They both use stem-loop structures formed in the RNA to stop or pause transcription.
(HAS AN IMAGE) Which tree topology is the most parsimonious with the genetic data? A) Tree topology #1 B) Tree topology #2 C) Tree topology #3 D) Tree topology #4
C) Tree topology #3
In a family, out of the eight children (5 male and 3 female), four sons have a particular genetic disease but none of the other siblings or the parents are affected. What is the likely mode of inheritance? (Hint: The mother's father had the genetic disease.) A) Autosomal recessive B) Autosomal dominant C) X-linked recessive D) X-linked dominant E) Epigenetic mechanisms
C) X-linked recessive
(HAS AN IMAGE) If this pedigree shows a dominant disorder caused by the dominant A allele, what are the genotypes of the parents in this pedigree? A) aa and AA B) Aa and Aa C) aa and Aa D) aa and aa
C) aa and Aa
The production of wild-type offspring from a cross between parents that both display the same recessive phenotype illustrates the genetic phenomenon of _______. A) gene dosage B) a spontaneous mutation C) complementation D) incomplete penetrance E) simple recessive allele
C) complementation
Migration of a random few individuals from one population to a new area to establish a new population is an example of __________. A) bottleneck effect B) mutation C) founder effect D) selection
C) founder effect
You are studying a new strain of bacteria. You discover that its genome contains some genes that are not found in any form in its most recent ancestor. You suspect __________. A) anagenesis B) an extremely high rate of mutation C) horizontal gene transfer D) cladogenesis
C) horizontal gene transfer
An individual carries the allele for polydactyly, a dominant trait, but is phenotypically normal. This is an example of __________. A) gene dosage B) codominance C) incomplete penetrance D) simple Mendelian inheritance E) incomplete dominance
C) incomplete penetrance
The bicoid gene, which establishes anterior-posterior axes in the early Drosophila embryo, has what pattern of inheritance? A) sex-linked B) incomplete penetrance C) maternal effect D) autosomal
C) maternal effect
The splicing reactions require the breaking and re-making of ... A) peptide bonds. B) disulfide bonds. C) phosphodiester bonds. D) glycosidic bonds. E) james bonds.
C) phosphodiester bonds.
In Drosophila, the genes reduced (rd) bristles and withered (whd) wing are both found on chromosome 2. You have isolated a new recessive mutation in Drosophila that results in corrugated (corr) veins. χ2-analysis has revealed that corr is linked to the genes rd and whd on Chr. 2. You perform a three-point cross to determine the relative order of the three genes. Two pure-breeding mutant lines were crossed to produce an F1 female that is normal in appearance for all three traits. The phenotypes of 1000 progeny resulting from a testcross of an F1 female are summarized below. 380 withered, reduced 385 corrugated 44 withered, corrugated 41 reduced 7 withered 8 corrugated, reduced 65 wildtype 70 withered, corrugated, reduced Which gene is in the middle? A) corr B) whd C) rd
C) rd
The pedigree below shows the inheritance pattern of a rare genetic disorder that is inherited in an X-linked dominant manner through one family. The filled in circles and squares show affected individuals. What is the probability of individual III-2 being born male and affected? A) 1/4 B) 1/2 C) 1/3 D) 0
D) 0
You are studying a diploid organism that has 14 pairs of chromosomes. How many chromatids will a gamete from this organism have? A) 7 B) 28 C) 56 D) 14 E) 112
D) 14
If a double-stranded DNA molecule is 22% G, what percent of the bases is A? A) 22% B) 44% C) 11% D) 28% E) 56%
D) 28%
Two pea plants that are heterozygous for the dominant tall gene and the dominant purple flower gene are mated. The cross resulted in 9866 progeny, of which 5550 were tall with purple flowers. What are the expected ratios of the other phenotypic classes? A) 5550 short/white flower, 5550 tall/white flower, 5550 short/purple flower B) 1850 short/white flower, 616 tall/white flower, 1850 short/purple flower C) 1850 short/white flower, 1850 tall/white flower, 1850 short/purple flower D) 616 short/white flower, 1850 tall/white flower, 1850 short/purple flower
D) 616 short/white flower, 1850 tall/white flower, 1850 short/purple flower
(HAS AN IMAGE) The wild-type mRNA has the following sequence in the middle of the transcript/coding region: GUGGCCGGACUUUUUGCC Which of the following are possible amino acids encoded by this sequence (use the Genetic Code table included in the exam)? A) ...Trp, Pro, Asp, Phe, Leu, Pro... B) ...Val, Ala, Gly, Leu, Phe, Ala... C) ...Gly, Arg, Thr, Phe, Cys... D) All of the above. E) None of the above.
D) All of the above.
Which of the following is not an example of euploidy? A) Diploid B) Triploid C) Polyploid D) Aneuploid E) Tetraploid
D) Aneuploid
In multicellular eukaryotic organisms, what distinguishes one cell type from another (example: skin vs. liver cells)? A) The genotype of parents B) The phenotype of parents C) Extranuclear DNA D) Differences in gene regulation, including which genes are expressed or not expressed E) Which X chromosome is inactivated
D) Differences in gene regulation, including which genes are expressed or not expressed
Given the following sequence of genes on a chromosome, determine what change in chromosome structure occurred. (The * indicates the centromere.) before A B C D * E F G H after A B C D * E F E F G H A) Inversion B) Deletion C) Translocation D) Duplication
D) Duplication
Under which of the following conditions will the lac operon have the highest expression? A) Glucose present, lactose absent B) Glucose present, lactose present C) Glucose absent, lactose absent D) Glucose absent, lactose present E) None of the above
D) Glucose absent, lactose present
A DNA-binding protein recognizes a specific sequence of nucleotide bases. Which region in the double-helical structure of DNA would it most likely binding and "recognize" the sequence? A) 5' end. B) 3' end C) Minor groove D) Major groove E) Intermediate groove
D) Major groove
What type of inheritance is observed with extranuclear DNA? A) Mendelian inheritance B) Sex-linked inheritance C) Paternal inheritance D) Maternal inheritance E) Maternal effect
D) Maternal inheritance
Which type of mutation is the most likely to give rise to a new allele for a gene? A) Silent B) Nonsense C) Frameshift D) Missense E) Common sense
D) Missense
Protein synthesis proceeds in the... A) 5' to 3' direction B) 3' to 5' direction C) C to N direction D) N to C direction E) None of the above. There is no directionality in protein synthesis
D) N to C direction
Which of the following is primarily responsible for the maternal effect as seen in snail shell coiling? A) Sperm cells B) Oocytes C) Placental cells D) Nurse cells E) Fibroblasts
D) Nurse cells
Which of the following statements about RNA synthesis and processing is false? A) A poly-A tail is added by the poly-A polymerase at the end of eukaryotic mRNA synthesis. B) "Capping" of the mRNA is found in eukaryotic cells. C) Removal of introns and splicing of the remaining exons are essential steps in generating the completed mRNA in eukaryotes. D) RNA synthesis during transcription occurs from 3' to 5' while the template strand is read from 5' to 3'. E) None. All of the above statements are true.
D) RNA synthesis during transcription occurs from 3' to 5' while the template strand is read from 5' to 3'.
In Rho-dependent termination... A) Rho binds to the operator and represses transcription. B) Rho binds to the rut site on the coding strand. C) Rho binds to the rut site on the template strand. D) Rho binds to the rut site on the mRNA. E) Rho binds to galactosides and regulates the lac operon.
D) Rho binds to the rut site on the mRNA.
What is the goal of functional genomics? A) To make genomics more functional B) To sequence the genomes of living organisms C) To identify genetic variations in human populations D) To determine the function or role of every gene E) To develop technologies to sequence genomes faster
D) To determine the function or role of every gene
Which of the following statements regarding the origin of replication in E. coli, oriC, is/are true? A) It is a DNA sequence. B) It is bound by the DnaA protein. C) Binding of DnaA causes the strands in the G-C rich sequence to separate. D) Two of the above E) All of the above
D) Two of the above
The wobble hypothesis... A) addresses degeneracy in the third base of some codons. B) explains why different codons code for the same amino acid. C) is partly explained by the presence of the inosine base in the anticodons. D) Two of the above. E) All of the above.
D) Two of the above.
(HAS AN IMAGE) What is the most likely mode of transmission for the following trait? Assume the trait is rare in the population. A) Autosomal dominant B) Autosomal recessive C) X-linked dominant D) X-linked recessive
D) X-linked recessive
Chromosomal deletions and duplications are frequently the result of __________. A) non-homologous chromosomes exchanging pieces B) the use of colchicine C) failure to separate chromosomes during anaphase D) abnormal crossover events
D) abnormal crossover events
The _______ of a morphogen determines its effect on development. A) size B) homeodomain C) color D) concentration
D) concentration
A testcross is always performed between the individual that is heterozygous for the genes to be mapped and an individual who is ____________. A) heterozygous for the genes B) lacking the genes C) homozygous dominant for the genes D) homozygous recessive for the genes
D) homozygous recessive for the genes
The Law of Independent Assortment states that __________. A) two different genes will NOT randomly assort their alleles during the formation of haploid cells B) two different alleles will randomly assort during the formation of haploid cells C) two different genes will randomly assort their alleles during the formation of diploid cells D) two different genes will randomly assort their alleles during the formation of haploid cells
D) two different genes will randomly assort their alleles during the formation of haploid cells
Which of the following is NOT a mechanism of gene regulation in bacteria? A) Regulatory proteins can bind to DNA and decrease transcription. B) Proteins or RNAs can bind to mRNA and prevent translation. C) Modifications of their protein products can alter their functions. D) Regulatory proteins can bind to DNA and increase transcription. E) 5' capping of RNA can regulate their stability and translation.
E) 5' capping of RNA can regulate their stability and translation.
Meiosis differs from mitosis in that: A) mitosis results in two daughter cells whereas meiosis results in four. B) daughter cells resulting from meiosis has half the number of chromosomes. C) daughter cells resulting from mitosis are genetically identical. D) Two from A, B and C. E) All of A, B and C
E) All of A, B and C
Bioinformatics utilizes computer algorithms to analyze genomic data. Which of the following types of sequences is used by sequence recognition algorithms to determine whether the sequence of a particular region of a eukaryotic genome encodes a gene? A) Promoters B) Splice sites C) Start and stop codons D) Polyadenylation signal. E) All of the above
E) All of the above
Chromatin remodeling in eukaryotes can result in what type of changes to the chromatin? A) Change in the position of nucleosomes B) Eviction of histone octamers C) Change in the histone composition of nucleosomes D) Makes the DNA more or less amenable to transcription E) All of the above
E) All of the above
What would be required to express a human protein-coding gene, such as the one that codes for erythropoietin, in bacteria? A) A bacterial promoter B) A bacterial terminator C) Addition of the Shine-Delgarno sequence to the beginning of the gene D) Removal of intronic sequences E) All of the above
E) All of the above
Which of the following was the justification given for requesting the $3 billion funding for the Human Genome Project? A) Scientific discovery B) Technological advancement C) Improvements to human health D) Economic impact E) All of the above
E) All of the above
Which of the following is NOT a mechanism of gene regulation in eukaryotes? A) Regulatory proteins can bind to DNA and decrease transcription. B) 5' capping of RNA can regulate their stability and translation. C) Modifications of their protein products can alter their functions. D) Regulatory proteins can bind to DNA and increase transcription. E) All of the above are gene regulation mechanisms in eukaryotes.
E) All of the above are gene regulation mechanisms in eukaryotes.
How are malignant tumors different from benign ones? A) Malignant tumors have invaded into surrounding tissue. B) Malignant tumors can potentially metastasize to distant sites. C) Malignant tumors are known as cancers. D) Malignant tumors have picked up more gene mutations. E) All of the above.
E) All of the above.
How can a proto-oncogene be turned into an oncogene? A) Missense mutations B) Gene amplifications C) Chromosome translocations D) Viral integration E) All of the above.
E) All of the above.
Non-coding RNAs can carry out their functions by interacting with which of the following types of molecules? A) DNA B) RNA C) Protein D) Small molecule/chemical compound E) All of the above.
E) All of the above.
Which small molecule functions as the inducer which binds the lac repressor in the regulation of the lac operon? A) cAMP. B) GTP C) ATP D) Galactose E) Allolactose
E) Allolactose
(HAS AN IMAGE) You have performed the following three point test cross in maize with the sugary (su), lazy (lz), and glossy (gl) genes. You want to infer the order and distance between genes. (Note: alleles in lower case are recessive; order alleles are written is not necessarily their order on the chromosome.)Which of the following maps is accurate for this trihybrid cross (numbers indicate map units): A) Su 10.7, Gl 0.8, Lz B) Lz 14.7, Su 23.6, Gl C) Su 14.7, Gl 23.6, Lz D) Gl 10.7, Lz 14.7, Su E) Lz 10.7, Su 14.7, Gl
E) Lz 10.7, Su 14.7, Gl
In the Nirenberg and Leder experiment to identify which charged tRNA binds to which codon in the ribosome, what should have been the result when they added the RNA with one the stop codon sequences? A) The initiator tRNA charged with methionine is bound to the ribosome. B) The tRNA charged with the release factor is bound. C) The terminator tRNA charged with glycine is bound. D) The terminator tRNA charged with phenylalanine is bound. E) No tRNA is bound to the ribosome.
E) No tRNA is bound to the ribosome.
In the Meselson and Stahl experiment, what would their results have looked like after one generation of DNA replication if, hypothetically, the mode of replication is conservative? A) Only light band B) Only heavy band C) Only half heavy (intermediate) band D) One half heavy and one light band E) One heavy and one light band
E) One heavy and one light band
Which of the following is NOT a characteristic by which a population is in equilibrium according to Hardy-Weinberg equation? A) The population is large B) There is no migration into or out of the population C) There is no selection against a given genotype D) There is no mutation in the gene being studied E) There is nonrandom mating
E) There is nonrandom mating
Biotechnology using the knowledge and tools of molecular genetics have resulted in genetically modified organisms which make products that benefit mankind. The creation and use of GMOs can be problematic or controversial because of... A) safety concerns. B) the difficulties in creating GMOs. C) negative public perceptions. D) the poor performance of GMOs in delivering the promised products. E) Two of the above
E) Two of the above
CRISPR-Cas technology is used in genetic engineering and biotechnology for which specific purposes? A) Edit gene sequences B) Inactivate genes C) Prevent homologous recombination D) Improve existing drugs E) Two of the above
E) Two of the above
Which of the following are responsible for the alignment of the start codon in the P site of the ribosome in bacteria? A) Elongation factors B) The Shine-Dalgarno sequence C) The 16 S rRNA D) Rho protein E) Two of the above
E) Two of the above
Which of the listed examples below demonstrates that RNA can function as an enzyme? A) Group I and II self-splicing introns B) Ribosomal RNA catalyzing the formation of peptide bonds during protein synthesis C) Cutting of target DNA sequence by CRISPR RNA D) 3' to 5' exonuclease activity of RNA polymerase E) Two of the above
E) Two of the above
Please select the correct matches of regulatory proteins and their corresponding regulatory elements/sequences in eukaryotes: A) Activators - Silencers B) Activators - Enhancers C) Repressors - Silencers D) Repressors - Enhancers E) Two of the above are correct
E) Two of the above are correct
Which of the following can be concluded regarding orthologous genes (orthologs)? A) They are derived from the same ancestral gene. B) They are likely to have the same or very similar functions. C) They are found in the same species. D) They are usually involved in human diseases. E) Two of the above.
E) Two of the above.
*For a repressible gene in bacteria, the binding of a small molecule corepressor to a repressor... A) prevents it from binding to DNA. B) helps it bind to DNA. C) inhibits gene transcription. D) prevents RNA polymerase from binding to the promoter. E) two of the above
E) two of the above
