Quiz 9 Flashcards
Assume that you are trying to insert a gene into a plasmid. Someone gives you a preparation of genomic DNA that has been cut with restriction enzyme X. The gene you wish to insert has sites on both ends for cutting by restriction enzyme Y. You have a plasmid with a single site for Y, but not for X. Your strategy should be to
a) insert the fragments cut with restriction enzyme X directly into the plasmid without cutting the plasmid.
b) cut the plasmid with restriction enzyme X and insert the fragments cut with restriction enzyme Y into the plasmid.
c) cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme.
d) cut the plasmid twice with restriction enzyme Y and ligate the two fragments onto the ends of the DNA fragments cut with restriction enzyme X.
c) cut the DNA again with restriction enzyme Y and insert these fragments into the plasmid cut with the same enzyme.
In order to identify a specific restriction fragment using a probe, what must be done?
a) The probe must be separated by electrophoresis, the fragments must be treated with heat or chemicals to separate the strands of the double helix, and the probe must be hybridized with the fragment.
b) The fragments must be separated by electrophoresis, the probe must be treated with heat or chemicals to separate the strands of the double helix, and the probe must be hybridized with the fragment.
c) The fragments must be separated by electrophoresis, the fragments must be treated with heat or chemicals to separate the strands of the double helix, and the probe must be hybridized with the fragment.
d) The probe must be separated by electrophoresis, the probe must be treated with heat or chemicals to separate the strands of the double helix, and the probe must be hybridized with the fragment.
c) The fragments must be separated by electrophoresis, the fragments must be treated with heat or chemicals to separate the strands of the double helix, and the probe must be hybridized with the fragment.
Which of the following problems with animal cloning might result in premature death of the clones?
a) use of pluripotent instead of totipotent stem cells
b) use of nuclear DNA as well as mitochondrial DNA
c) abnormal regulation due to variant methylation
d) the indefinite replication of totipotent stem cells
c) abnormal regulation due to variant methylation
One possible use of transgenic plants is in the production of human proteins, such as vaccines. Which of the following is a possible hindrance that must be overcome?
a) prevention of transmission of plant allergens to the vaccine recipients
b) prevention of vacciine-containing plants being consumed by insects
c) use of plant cells to translate non-plant-derived mRNA
d) inability of the human digestive system to accept plant-derived protein
a) prevention of transmission of plant allergens to the vaccine recipients
What is bioinformatics?
a) a method that uses very large national and international databases to access and work with sequence information
b) a software program available from NIH to design genes
c) a series of search programs that allow a student to identify who in the world is trying to sequence a given species
d) a procedure that uses software to order DNA sequences in a variety of comparable ways
a) a method that uses very large national and international databases to access and work with sequence information
Which of the following studies would NOT likely be characterized as eco-devo?
a) a study of the assortment of homeotic genes in the zebra
b) a comparison of the functions of a particular homeotic gene among four species of reptiles
c) studying the environmental pressures on developmental stages such as the tadpole
d) a fossil comparison of organisms from the Devonian era.
b) a comparison of the functions of a particular homeotic gene among four species of reptiles
In DNA technology, the term vector can refer to
a) the enzyme that cuts DNA into restriction fragments.
b) the sticky end of a DNA fragment.
c) a SNP marker.
d) a plasmid used to transfer DNA into a living cell.
d) a plasmid used to transfer DNA into a living cell.
Which of the following tools of DNA technology is INCORRECTLY paired with its use?
a) electrophoresis-separation of DNA fragments
b) DNA ligase-cutting DNA, creating sticky ends of restriction fragments
c) DNA polymerase-polymerase chain reaction to amplify sections of DNA
d) reverse transcriptase-production of cDNA from mRNA
b) DNA ligase-cutting DNA, creating sticky ends of restriction fragments
Plants are more readily manipulated by genetic engineering than are animals because
a) plant genes do not contain introns.
b) more vectors are available for transferring recombinant DNA into plant cells.
c) a somatic plant cell can often give rise to a complete plant.
d) plant cells have larger nuclei.
c) a somatic plant cell can often give rise to a complete plant.
A paleontologist has recovered a bit of tissue from the 400-year-old preserved skin of an extinct dodo (a bird). To compare a specific region of the DNA from a sample with DNA from living birds, which of the following would be most useful for increasing the amount of dodo DNA available for testing?
a) SNP analysis
b) polymerase chain reaction (PCR)
c) electroporation
d) gel electrophoresis
b) polymerase chain reaction (PCR)
DNA technology has many medical applications. Which of the following is NOT done routinely at present?
a) production of hormones for treating diabetes and dwarfism
b) production of microbes that can metabolize toxins
c) introduction of genetically engineered genes into human gametes
d) prenatal identification of genetic disease alleles
c) introduction of genetically engineered genes into human gametes
Which of the following would not be true of cDNA produced using human brain tissue as the starting material?
a) It could be amplified by the polymerase chain reaction.
b) It was produced from pre-mRNA using reverse transcriptase.
c) It could be labelled and used as a probe to detect genes expressed in the brain.
d) It lacks the introns of the pre-mRNA.
b) It was produced from pre-mRNA using reverse transcriptase.
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
a) post-transcriptional processing.
b) post-translational processing.
c) nucleic acid hybridization.
d) restriction fragment ligation.
a) post-transcriptional processing.
Which of the following sequences in double-stranded DNA is most likely to be recognized as a cutting site for a restriction enzyme?
a) AAGG
TTCC
b) GGCC
CCGG
c) ACCA
TGGT
d) AAAA
TTT
b) GGCC
CCGG
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 a 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
Genetically engineered plants
a) are able to fix nitrogen themselves.
b) are banned throughout the world.
c) are more difficult to engineer than animals.
d) are being rapidly developed, but traditional plant breeding programs are still the only method used to develop new plants.
e) include a transgenic rice plant that can help prevent vitamin A deficiency.
e) include a transgenic rice plant that can help prevent vitamin A deficiency.
Which of the following is one of the technical reasons why gene therapy is problematic?
a) Cells with transferred genes are unlikely to replicate.
b) Most cells with an engineered gene do not produce gene product.
c) Transferred genes may not have appropriately controlled activity.
d) mRNA from transferred genes cannot be translated.
e) Most cells with engineered genes overwhelm other cells in a tissue.
c) Transferred genes may not have appropriately controlled activity.
Which of the following best describes the complete sequence of steps occurring during every cycle of PCR?
- The primers hybridize to the target DNA.
- The mixture is heated to a high temperature to denature the double-stranded target DNA.
- Fresh DNA polymerase is added.
- DNA polymerase extends the primers to make a copy of the target DNA.
2, 1, 4
