EXAM 4: QUIZ METHODS: DNA Flashcards
Genetically engineered plants
include a transgenic rice plant that can help prevent vitamin A deficiency.
Which of the following procedures would produce RFLPs?
incubating DNA with restriction enzymes
In recombinant DNA methods, the term vector can refer to
a plasmid used to transfer DNA into a living cell.
Sequencing an entire genome, such as that of C. elegans, a nematode, is most important because
a sequence that is found to have a particular function in the nematode is likely to have a closely related function in vertebrates.
How does a genomic library differ from a cDNA library?
g library can be made using a restriction enzyme and DNA ligase only, whereas a cDNA library requires both of these as well as reverse transcriptase and DNA polymerase.
Imagine you want to study human crystallins, proteins present in the lens of the eye. To obtain a sufficient amount of the protein, you decide to clone the crystallin gene. Would you construct a genomic library or a cDNA library? What material would you use as a source of DNA or RNA?
mRNA from human lens cells
Which of the following best describes the complete sequence of steps occurring during every cycle of PCR? 1. The primers hybridize to the target DNA. 2. The mixture is heated to a high temperature to denature the double stranded target DNA. 3. Fresh DNA polymerase is added. 4. DNA polymerase extends the primers to make a copy of the target DNA.
2, 1, 4
To introduce a particular piece of DNA into an animal cell, such as that of a mouse, you would find more probable success with which of the following methods?
electroporation followed by recombination
Which of the following is true of embryonic stem cells but not of adult stem cells?
They make up the majority of cells of the tissue from which they are derived.
Which uses reverse transcriptase to make cDNA followed by amplification?
RT-PCR
CML (chronic myelogenous leukemia) results from a translocation between human chromosomes 9 and 22. The resulting chromosome 22 is significantly shorter than the usual, and it is known as a Philadelphia (Ph’) chromosome. The junction at the site of the translocation causes over-expression of a thymine kinase receptor. A new drug (Gleevec or imatinib) has been found to inhibit the disease if the patient is treated early. Why would Gleevec most probably cause remission of the disease?
The drug inhibits the specific thymine kinase receptor.
In 1997, Dolly the sheep was cloned. Which of the following processes was used?
fusion of an adult cell’s nucleus with an enucleated sheep egg, followed by incubation in a surrogate
A eukaryotic gene has “sticky ends” produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original. Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline, and nutrient broth without antibiotics. Bacteria that do not take up any plasmids would grow on which media?
the nutrient broth only
What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium? I. Transform bacteria with recombinant DNA molecule. II. Cut the
plasmid DNA using restriction enzymes. III. Extract plasmid DNA from bacterial cells. IV. Hydrogen-bond the plasmid DNA to nonplasmid DNA fragments. V. Use ligase to seal plasmid DNA to nonplasmid DNA.
III, II, IV, V, I
Expression of a cloned eukaryotic gene in a bacterial cell involves many challenges. The use of mRNA and reverse transcriptase is part of a strategy to solve the problem of
post-transcriptional processing.
Which was developed by a British researcher and causes DNA sequences to be transferred to a membrane and identified with a probe?
Southern blotting
DNA microarrays have made a huge impact on genomic studies because they
allow the expression of many or even all of the genes in the genome to be compared at once.
Which of the following techniques used to analyze gene function depends on the specificity of DNA base complementarity?
in vitro mutagenesis
Which seals the sticky ends of restriction fragments to make recombinant DNA?
DNA ligase
Which of the following separates molecules by movement due to size and electrical charge?
gel electrophoresis
Which of the following is one of the technical reasons why gene therapy is problematic?
Transferred genes may not have appropriately controlled activity.
Imagine you want to study human crystallins, proteins present in the lens of the eye. To obtain a sufficient amount of the protein, you decide to clone the crystallin gene. Would you construct a genomic library or a cDNA library?
cDNA library
Which of the following is used to make complementary DNA (cDNA) from RNA?
reverse transcriptase
Gene therapy
had apparent success in treating disorders involving bone marrow cells.
A eukaryotic gene has “sticky ends” produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original. Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline, and nutrient broth without antibiotics. Bacteria containing a plasmid into which the eukaryotic gene has integrated would grow in
the ampicillin broth and the nutrient broth.