Genetics final exam prep, (Answered) With Complete Verified Solutions

Genetics final exam prep, (Answered) With Complete Verified Solutions 1. Place the steps of generating a gene - knockout mouse in order from the dis- ruption of the target gene to generat- ing homozygous knockouts. Suppose in 1. Disrupt target gene by insert- ing neo+ and link tk+ to disrupted gene 2. transfer disrupted gene into one experiment, the stem cells used are stem cells from a black mouse from a black coated mouse, and the earl3y. allow recombination with mouse embryo used is a white coated embryo. 2. A geneticist isolates a new restriction enzyme from the bacterium Aeromonas ranidae. No other restriction enzymes have been isolated from this bacterial species. Use the standard convention for abbre- viating restriction enzymes to name this new restriction enzyme. 3. Suppose a scientist wants to clone the gene for human insulin. He uses a plas- mid that contains the lacZ gene, an ori- gin of replication, and an ampicillin re- sistant gene. He inserts the human in- sulin gene into a restriction site locat- ed within the lacZ gene. Then he trans- forms this plasmid into bacteria with- out a functional lacZ gene and spreads the appropriate dilution onto bacterial plates. genome to generate neo+ tk- cells 4. select for neo+ and select against tk+ to isolate cells from homologous recombination 5. inject neo+ cells into white ear- ly embryo and implant into surro- gate 6. identify chimeric progeny with target-gene knockout cells 7. breed mice to generate ho- mozygous knockouts AraI an LB agar plate with ampicillin and X-Gal that produces color- less colonies When the product of the lacZ gene, be- ta galactosidase, interacts with the sub- trate X Gal on LB agar, colonies turn blue. Which plate indicates that the human insulin gene was successfully inserted in the plasmid? 4. Plasmids are small circular DNA mol- ecules found in bacteria that replicate separately from chromosomes. Why are plasmids essential for recombi- nant DNA technology? 5. Polymerase chain reaction (PCR) is a technique used to amplify (copy) DNA. Suppose a single, linear molecule of DNA from a gene of interest can be inserted into a plasmid, then the modified plasmid can be in- serted into a bacterial cell to repli- cate a gene of interest many times 2 double stranded DNA (dsDNA) is ampli- fied by PCR. After one PCR cycle, how many mole- cules of dsDNA will there be? molecules of dsDNA after one cycle: 6. After three PCR cycles, how many mol- 8 ecules of dsDNA will there be? 7. After 30 PCR cycles (a typical number of ~1 billion cycles), how many molecules of dsDNA will there be? 8. Consider that a typical PCR does not start with a single molecule of template DNA, but rather something in the range of 25 nmol of template DNA. What does this tell you about the poten- tial of PCR to amplify DNA? 9. Suppose a scientist is studying the platypus, one of the few venomous PCR is an efficient technique with the potential to produce a large amount of DNA mammals. The male platypus produces venom in the crural glands located be- neath the calcaneus spur on each of its hind limbs. The female platypus can de- velop calcaneous spurs, but the crural glands never develop. Which of the following libraries would be most useful to help the scientist iden- tify the gene or genes responsible for venom production? cDNA library made from the mRNA isolated from the crural gland of a male platypus 10. Identify examples of reverse genetics. - gene knockout using site direct- ed mutagenesis - RNA interference 11. Which statement represents the defini- tion of a reversion (reverse mutation)? 12. Researchers construct different types of genomic maps to gain information about genes and their locations in the genome. Why would a researcher choose to con- struct a physical map of genes rather than a genetic map? 13. The field of genomics encompasses several methodologies used to study an organism's entire set of DNA, or genome. Classify each statement as a characteristic of comparative genomics 14. The field of genomics encompasses several methodologies used to study an organism's entire set of DNA, or genome. Classify each statement as a characteristic of functional genomics mutation from mutant allele to wild-type allele to determine the locations of spe- cific genes on a chromosome and the distance between them analyzes multiple genomes to de- termine gene functions examines evolutionary relation- ships between organisms investigates the cellular roles of genes and gene products focuses on transcription and translation 15. The field of genomics encompasses several methodologies used to study an organism's entire set of DNA, or genome. Classify each statement as a characteristic of structural genomics 16. Most scientists consider the Human Genome Project (HGP) to be the most significant scientific project of the 21st century. Choose the statements that describe the key findings of the Human Genome Project. 17. With current sequencing technology, contigs are integral to understanding the entire genome of an organism. What is a contig? 18. The genome of Drosophila melanogaster, a fruit fly, was sequenced in 2000. However, this sequence con- sisted mainly of euchromatin. The het- erochromatin was not sequenced un- til 2007. Most completed genome se- quences do not include heterochro- matin. Why is heterochromatin usually not se- quenced in genomic projects? 19. Which description is the best definition of a single nucleotide polymorphism, or SNP? 20. Suppose that archaeologists find a tomb in Egypt containing a mummy. The tomb has been looted and any identify- ing hieroglyphs on the walls have worn away. The mummy does not have any visible distinguishing features, but her focuses on determining the nu- cleotide sequence of a genome concerns the physical organiza- tion of DNA the human genome contains ap- proximately 25000 genes there are approximately three bil- lion base pairs in the human genome overlapping DNA fragments con- structed into a continuous DNA sequence Heterochromatin contains many short repeated sequences, which makes it difficult to assemble heterochromatin sequences into large contigs when the nucleotide at a partic- ular genomic position differs be- tween two individuals use genome analysis to compare her DNA with DNA from other identified mummies in the area tissues still contain intact DNA. What could scientists do to identify who this mummy was? 21. After discovering a gene for the pro- duction of fur in mammals and examin- ing the gene regulation in the genomes of a monkey, bear, zebrafish, wolf, and snake, it is evident that all of the genomes have an orthologous gene. Select the statements that show what analysis of the orthologous gene says about the function of the gene control- ling the trait. 22. Order the steps required to analyze gene expression from a particular cell type using a DNA microarray. 23. How does comparative genomics aid in the search for factors that contribute to complex human conditions? 24. As depicted in the table, certain plant genomes are significantly larger than mammal genomes, including the human genome. Why do these diploid plants have more DNA, but less organismal complexity compared with humans? 25. Classify each characteristic as being commonly found in bacterial genomes the ancestral form of the gene was potentially involved in a differ- ent biological function the gene function is not limited to fur production 1. extract mRNA from cells 2. reverse transcribe mRNA to cDNA 3. label cDNA with a chemilumi- nescent molecule 4. add cDNA to microarray and incubate 5. wash away unbound cDNA 6. visualize microarray and ana- lyze resulting data Conserved genetic sequences likely influence similar phenotypic traits across species repetitive DNA from transposons accounts for the majority of these plant genomes most have a circular chromosome have very few noncoding regions