5) A gene that contains introns can be made shorter (but remain functional) for genetic engineering
purposes by using
A) RNA polymerase to transcribe the gene.
B) a restriction enzyme to cut the gene into shorter pieces.
C) reverse transcriptase to reconstruct the gene from its mRNA.
D) DNA polymerase to reconstruct the gene from its polypeptide product.
E) DNA ligase to put together fragments of the DNA that code for a particular polypeptide.

C

6) Why are yeast cells frequently used as hosts for cloning?
A) They easily form colonies.
B) They can remove exons from mRNA.
C) They do not have plasmids.
D) They are eukaryotic cells.
E) Only yeast cells allow the gene to be cloned.

D

7) The DNA fragments making up a genomic library are generally contained in
A) BACs.
B) recombinant viral RNA.
C) individual wells.
D) DNA-RNA hybrids.
E) radioactive eukaryotic cells.

A

8) Yeast artificial chromosomes contain which of the following elements?
A) centromeres only
B) telomeres only
C) origin of replication only
D) centromeres and telomeres only
E) centromeres, telomeres, and an origin of replication

E

9) 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.
A) 2, 1, 4
B) 1, 3, 2, 4
C) 3, 4, 1, 2
D) 3, 4, 2
E) 2, 3, 4

A

10) A researcher needs to clone a sequence of part of a eukaryotic genome in order to express the
sequence and to modify the polypeptide product. She would be able to satisfy these requirements by
using which of the following vectors?
A) a bacterial plasmid
B) BAC to accommodate the size of the sequence
C) a modified bacteriophage
D) a human chromosome
E) a YAC with appropriate cellular enzymes

E

11) A student wishes to clone a sequence of DNA of ~200 kb. Which vector would be appropriate?
A) a plasmid
B) a typical bacteriophage
C) a BAC
D) a plant virus
E) a large polypeptide

C

12) Sequencing an entire genome, such as that of C. elegans, a nematode, is most important because
A) it allows researchers to use the sequence to build a "better" nematode, which is resistant to disease.
B) it allows research on a group of organisms we do not usually care much about.
C) the nematode is a good animal model for trying out cures for viral illness.
D) a sequence that is found to have a particular function in the nematode is likely to have a closely
related function in vertebrates.
E) a sequence that is found to have no introns in the nematode genome is likely to have acquired the
introns from higher organisms.

D

13) 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?
A) the shotgun approach
B) electroporation followed by recombination
C) introducing a plasmid into the cell
D) infecting the mouse cell with a Ti plasmid
E) transcription and translation

B

14) The major advantage of using artificial chromosomes such as YACs and BACs for cloning genes is that

A) plasmids are unable to replicate in cells.

B) only one copy of a plasmid can be present in any given cell, whereas many copies of a YAC or BAC can coexist in a single cell.

C) YACs and BACs can carry much larger DNA fragments than ordinary plasmids can.

D) YACs and BACs can be used to express proteins encoded by inserted genes, but plasmids cannot.

E) All of these are correct.

C

15) Which of the following is used to make complementary DNA (cDNA) from RNA?

A) restriction enzymes

B) gene cloning

C) DNA ligase

D) gel electrophoresis

E) reverse transcriptase

E

16) Why is it so important to be able to amplify DNA fragments when studying genes?

A) DNA fragments are too small to use individually.

B) A gene may represent only a millionth of the cell's DNA.

C) Restriction enzymes cut DNA into fragments that are too small.

D) A clone requires multiple copies of each gene per clone.

E) It is important to have multiple copies of DNA in the case of laboratory error.

B

17) Pax-6 is a gene that is involved in eye formation in many invertebrates, such as Drosophila. Pax-6 is found as well in vertebrates. A Pax-6 gene from a mouse can be expressed in a fly and the protein (PAX-6) leads to a compound fly eye. This information suggests which of the following?

A) Pax-6 genes are identical in nucleotide sequence.

B) PAX-6 proteins have identical amino acid sequences.

C) Pax-6 is highly conserved and shows shared evolutionary ancestry.

D) PAX-6 proteins are different for formation of different kinds of eyes.

E) PAX-6 from a mouse can function in a fly, but a fly's Pax-6 gene cannot function in a mouse.

C

18) Why are BACs preferred today rather than bacteriophages for making genomic libraries?

A) The BAC carries more DNA.

B) The BAC can carry entire genes and their regulatory elements.

C) Larger BACs are easier to store.

D) The BAC can carry entire genes and their regulatory elements, and larger BACs are easier to store.

E) The BAC carries more DNA, the BAC can carry entire genes and their regulatory elements, and larger BACs are easier to store.

E

19) The reason for using Taq polymerase for PCR is that

A) it is heat stable and can withstand the temperature changes of the cycler.

B) only minute amounts are needed for each cycle of PCR.

C) it binds more readily than other polymerases to primer.

D) it has regions that are complementary to primers.

E) All of these are correct.

A

20) Why might a laboratory be using dideoxy nucleotides?

A) to separate DNA fragments

B) to clone the breakpoints of cut DNA

C) to produce cDNA from mRNA

D) to sequence a DNA fragment

E) to visualize DNA expression

D

21) In order to identify a specific restriction fragment using a probe, what must be done?

A) The fragments must be separated by electrophoresis.

B) The fragments must be treated with heat or chemicals to separate the strands of the double helix.

C) The probe must be hybridized with the fragment.

D) The fragments must be separated by electrophoresis and the fragments must be treated with heat or chemicals to separate the strands of the double helix.

E) 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.

E

22) Which of the following modifications is least likely to alter the rate at which a DNA fragment moves through a gel during electrophoresis?

A) altering the nucleotide sequence of the DNA fragment

B) methylating the cytosine bases within the DNA fragment

C) increasing the length of the DNA fragment

D) decreasing the length of the DNA fragment

E) neutralizing the negative charges within the DNA fragment

A

23) DNA fragments from a gel are transferred to a nitrocellulose paper during the procedure called Southern blotting. What is the purpose of transferring the DNA from a gel to a nitrocellulose paper?

A) to attach the DNA fragments to a permanent substrate

B) to separate the two complementary DNA strands

C) to transfer only the DNA that is of interest

D) to prepare the DNA for digestion with restriction enzymes

E) to separate out the PCRs

A

24) DNA microarrays have made a huge impact on genomic studies because they

A) can be used to eliminate the function of any gene in the genome.

B) can be used to introduce entire genomes into bacterial cells.

C) allow the expression of many or even all of the genes in the genome to be compared at once.

D) allow physical maps of the genome to be assembled in a very short time.

E) dramatically enhance the efficiency of restriction enzymes

C

25) Which of the following describes the transfer of polypeptide sequences to a membrane to analyze gene expression?

A) Southern blotting

B) Northern blotting

C) Western blotting

D) Eastern blotting

E) RT-PCR

C

26) Which of the following uses reverse transcriptase to make cDNA followed by amplification?

A) Southern blotting

B) Northern blotting

C) Western blotting

D) Eastern blotting

E) RT-PCR

E

27) RNAi methodology uses double-stranded pieces of RNA to trigger a breakdown or blocking of mRNA. For which of the following might it more possibly be useful?

A) to raise the rate of production of a needed digestive enzyme

B) to decrease the production from a harmful gain-of-function mutated gene

C) to destroy an unwanted allele in a homozygous individual

D) to form a knockout organism that will not pass the deleted sequence to its progeny

E) to raise the concentration of a desired protein

B

28) A researcher has used in vitro mutagenesis to mutate a cloned gene and then has reinserted this into a cell. In order to have the mutated sequence disable the function of the gene, what must then occur?

A) recombination resulting in replacement of the wild type with the mutated gene

B) use of a microarray to verify continued expression of the original gene

C) replication of the cloned gene using a bacterial plasmid

D) transcription of the cloned gene using a BAC

E) attachment of the mutated gene to an existing mRNA to be translated

A

29) Which of the following techniques used to analyze gene function depends on the specificity of DNA base complementarity?

A) Northern blotting

B) use of RNAi

C) in vitro mutagenesis

D) in situ hybridization

E) restriction fragment analysis

C

30) Silencing of selected genes is often done using RNA interference (RNAi). Which of the following questions would not be answered with this process?

A) What is the function of gene 432 in this species of annelid?

B) What will happen in this insect's digestion if gene 173 is not able to be translated?

C) Is gene HA292 responsible for this disorder in humans?

D) Will the disabling of this gene in Drosophila and in a mouse cause similar results?

E) Is the gene on Drosophila chromosome 2L at this locus responsible for part of its production of nitrogen waste?

C

31) In large scale, genome-wide association studies in humans, correlation is sought between

A) lengthy sequences that might be shared by most members of a population.

B) single nucleotide polymorphisms found only in persons with a particular disorder.

C) single nucleotide polymorphisms found in families with a particular introns sequence.

D) single nucleotide polymorphisms in two or more adjacent genes.

E) large inversions that displace the centromere.

B

32) For a particular microarray assay (DNA chip), cDNA has been made from the mRNAs of a dozen patients' breast tumor biopsies. The researchers will be looking for

A) a particular gene that is amplified in all or most of the patient samples.

B) a pattern of fluorescence that indicates which cells are overproliferating.

C) a pattern shared among some or all of the samples that indicates gene expression differing from control samples.

D) a group of cDNAs that act differently from those on the rest of the grid.

E) a group of cDNAs that match those in non-breast cancer control samples from the same population.

C

33) Which of the following is most closely identical to the formation of twins?

A) cell cloning

B) therapeutic cloning

C) use of adult stem cells

D) embryo transfer

E) organismal cloning

E

34) In 1997, Dolly the sheep was cloned. Which of the following processes was used?

A) use of mitochondrial DNA from adult female cells of another ewe

B) replication and dedifferentiation of adult stem cells from sheep bone marrow

C) separation of an early stage sheep blastula into separate cells, one of which was incubated in a surrogate ewe

D) fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate

E) isolation of stem cells from a lamb embryo and production of a zygote equivalent

D

35) 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 mtDNA

C) abnormal regulation due to variant methylation

D) the indefinite replication of totipotent stem cells

E) abnormal immune function due to bone marrow dysfunction

C

36) Reproductive cloning of human embryos is generally considered unethical. However, on the subject of therapeutic cloning there is a wider divergence of opinion. Which of the following is a likely explanation?

A) Use of adult stem cells is likely to produce more cell types than use of embryonic stem cells.

B) Cloning to produce embryonic stem cells may lead to great medical benefits for many.

C) Cloning to produce stem cells relies on a different initial procedure than reproductive cloning.

D) A clone that lives until the blastocyst stage does not yet have human DNA.

E) No embryos would be destroyed in the process of therapeutic cloning.

B

37) Which of the following is true of embryonic stem cells but not of adult stem cells?

A) They can differentiate into many cell types.

B) They make up the majority of cells of the tissue from which they are derived.

C) They can continue to replicate for an indefinite period.

D) They can provide enormous amounts of information about the process of gene regulation.

E) One aim of using them is to provide cells for repair of diseased tissue.

B

38) A researcher is using adult stem cells and comparing them to other adult cells from the same tissue. Which of the following is a likely finding?

A) The cells from the two sources exhibit different patterns of DNA methylation.

B) Adult stem cells have more DNA nucleotides than their counterparts.

C) The two kinds of cells have virtually identical gene expression patterns in microarrays.

D) The nonstem cells have fewer repressed genes.

E) The nonstem cells have lost the promoters for more genes.

A

39) In animals, what is the difference between reproductive cloning and therapeutic cloning?

A) Reproductive cloning uses totipotent cells, whereas therapeutic cloning does not.

B) Reproductive cloning uses embryonic stem cells, whereas therapeutic cloning does not.

C) Therapeutic cloning uses nuclei of adult cells transplanted into enucleated nonfertilized eggs.

D) Therapeutic cloning supplies cells for repair of diseased or injured organs.

D

40) The first cloned cat, called Carbon Copy, was a calico, but she looked significantly different from her female parent. Why?

A) The environment, as well as genetics, affects phenotypic variation.

B) Fur color genes in cats are influenced by differential acetylation patterns.

C) Cloned animals have been found to have a higher frequency of transposon activation

D) X inactivation in the embryo is random and produces different patterns.

E) The telomeres of the parent's chromosomes were shorter than those of an embryo.

D

41) In recent times, it has been shown that adult cells can be induced to become pluripotent stem cells (iPS). In order to make this conversion, what has been done to the adult cells?

A) A retrovirus is used to introduce four specific regulatory genes.

B) The adult stem cells must be fused with embryonic cells.

C) Cytoplasm from embryonic cells is injected into the adult cells.

D) An adenovirus vector is used to transfer embryonic gene products into adult cells.

E) The nucleus of an embryonic cell is used to replace the nucleus of an adult cell.

A

42) Let us suppose that someone is successful at producing induced pluripotent stem cells (iPS) for replacement of pancreatic insulin-producing cells for people with type 1 diabetes. Which of the following could still be problems?

I. the possibility that, once introduced into the patient, the iPS cells produce nonpancreatic cells

II. the failure of the iPS cells to take up residence in the pancreas

III. the inability of the iPS cells to respond to appropriate regulatory signals

A) I only

B) II only

C) III only

D) I and II

E) all of them

E

43) Genetic engineering is being used by the pharmaceutical industry. Which of the following is not currently one of the uses?

A) production of human insulin

B) production of human growth hormone

C) production of tissue plasminogen activator

D) genetic modification of plants to produce vaccines

E) creation of products that will remove poisons from the human body

E

44) Genetically engineered plants

A) are more difficult to engineer than animals.

B) include a transgenic rice plant that can help prevent vitamin A deficiency.

C) are being rapidly developed, but traditional plant breeding programs are still the only method used to develop new plants.

D) are able to fix nitrogen themselves.

E) are banned throughout the world.

B

45) Scientists developed a set of guidelines to address the safety of DNA technology. Which of the following is one of the adopted safety measures?

A) Microorganisms used in recombinant DNA experiments are genetically crippled to ensure that they cannot survive outside of the laboratory.

B) Genetically modified organisms are not allowed to be part of our food supply.

C) Transgenic plants are engineered so that the plant genes cannot hybridize.

D) Experiments involving HIV or other potentially dangerous viruses have been banned.

E) Recombinant plasmids cannot be replicated.

A

46) One successful form of gene therapy has involved delivery of an allele for the enzyme adenosine deaminase (ADA) to bone marrow cells of a child with SCID, and delivery of these engineered cells back to the bone marrow of the affected child. What is one major reason for the success of this procedure as opposed to many other efforts at gene therapy?

A) The engineered bone marrow cells from this patient can be used for any other SCID patient.

B) The ADA-introduced allele causes all other ADA-negative cells to die.

C) The engineered cells, when reintroduced into the patient, find their way back to the bone marrow.

D) No vector is required to introduce the allele into ADA-negative cells.

E) The immune system fails to recognize cells with the variant gene.

C

47) Which of the following is one of the technical reasons why gene therapy is problematic?

A) Most cells with an engineered gene do not produce gene product.

B) Most cells with engineered genes overwhelm other cells in a tissue.

C) Cells with transferred genes are unlikely to replicate.

D) Transferred genes may not have appropriately controlled activity.

E) mRNA from transferred genes cannot be translated.

D

48) As genetic technology makes testing for a wide variety of genotypes possible, which of the following is likely to be an increasingly troublesome issue?

A) use of genotype information to provide positive identification of criminals

B) using technology to identify genes that cause criminal behaviors

C) the need to legislate for the protection of the privacy of genetic information

D) discrimination against certain racial groups because of major genetic differences

E) alteration of human phenotypes to prevent early disease

C

49) Which enzyme was used to produce the molecule in Figure 20.1?

A) ligase

B) transcriptase

C) a restriction enzyme

D) RNA polymerase

E) DNA polymerase

C

B

51) Which of the following statements is consistent with the results?

A) B is the child of A and C.

B) C is the child of A and B.

C) D is the child of B and C.

D) A is the child of B and C.

E) A is the child of C and D.

B

52) Which of the following statements is most likely true?

A) D is the child of A and C.

B) D is the child of A and B.

C) D is the child of B and C.

D) A is the child of C and D.

E) B is the child of A and C.

B

53) Which of the following are probably siblings?

A) A and B

B) A and C

C) A and D

D) C and D

E) B and D

D

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.

54) Bacteria that contain the plasmid, but not the eukaryotic gene, would grow

A) in the nutrient broth plus ampicillin, but not in the broth containing tetracycline.

B) only in the broth containing both antibiotics.

C) in the broth containing tetracycline, but not in the broth containing ampicillin.

D) in all four types of broth.

E) in the nutrient broth without antibiotics only.

D

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.

55) Bacteria containing a plasmid into which the eukaryotic gene has integrated would grow in

A) the nutrient broth only.

B) the nutrient broth and the tetracycline broth only.

C) the nutrient broth, the ampicillin broth, and the tetracycline broth.

D) all four types of broth.

E) the ampicillin broth and the nutrient broth.

E

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.

56) Bacteria that do not take up any plasmids would grow on which media?

A) the nutrient broth only

B) the nutrient broth and the tetracycline broth

C) the nutrient broth and the ampicillin broth

D) the tetracycline broth and the ampicillin broth

E) all three broths

A

A group of six students has taken samples of their own cheek cells, purified the DNA, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest.

57) Why might they be conducting such an experiment?

A) to find the location of this gene in the human genome

B) to prepare to isolate the chromosome on which the gene of interest is found

C) to find which of the students has which alleles

D) to collect population data that can be used to assess natural selection

E) to collect population data that can be used to study genetic drift

C

A group of six students has taken samples of their own cheek cells, purified the DNA, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest.

58) Their next two steps, in order, should be

A) use of a fluorescent probe for the gene sequence, then electrophoresis.

B) electrophoresis of the fragments followed by autoradiography.

C) electrophoresis of the fragments, followed by the use of a probe.

D) use of a ligase that will anneal the pieces, followed by Southern blotting.

E) use of reverse transcriptase to make cDNA, followed by electrophoresis

C

A group of six students has taken samples of their own cheek cells, purified the DNA, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest.

59) Analysis of the data obtained shows that two students each have two fragments, two students each have three fragments, and two students each have one only. What does this demonstrate?

A) Each pair of students has a different gene for this function.

B) The two students who have two fragments have one restriction site in this region.

C) The two students who have two fragments have two restriction sites within this gene.

D) The students with three fragments are said to have "fragile sites."

E) Each of these students is heterozygous for this gene

B

CML (chronic myelogenous leukemia) results from a translocation between human chromosomes 9 and 22. The resulting chromosome 22 is significantly shorter than usual, and it is known as a Philadelphia (Ph') chromosome. The junction at the site of the translocation causes overexpression of a thymine kinase receptor. A new drug (Gleevec or imatinib) has been found to inhibit the disease if the patient is treated early.

60) Which of the following would be a reasonably efficient technique for confirming the diagnosis of CML?

A) searching for the number of telomeric sequences on chromosome 22

B) looking for a Ph' chromosome in a peripheral blood smear

C) enzyme assay for thymine kinase activity

D) FISH study to determine the chromosomal location of all chromosome 22 fragments

E) identification of the disease phenotype in review of the patient's records

D

CML (chronic myelogenous leukemia) results from a translocation between human chromosomes 9 and 22. The resulting chromosome 22 is significantly shorter than usual, and it is known as a Philadelphia (Ph') chromosome. The junction at the site of the translocation causes overexpression of a thymine kinase receptor. A new drug (Gleevec or imatinib) has been found to inhibit the disease if the patient is treated early.

61) Why would Gleevec most probably cause remission of the disease?

A) It reverses the chromosomal translocation.

B) It eliminates the Ph' chromosome.

C) It removes Ph'-containing progenitor cells.

D) The drug inhibits the replication of the affected chromosome.

E) The drug inhibits the specific thymine kinase receptor.

E

CML (chronic myelogenous leukemia) results from a translocation between human chromosomes 9 and 22. The resulting chromosome 22 is significantly shorter than usual, and it is known as a Philadelphia (Ph') chromosome. The junction at the site of the translocation causes overexpression of a thymine kinase receptor. A new drug (Gleevec or imatinib) has been found to inhibit the disease if the patient is treated early.

62) 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 vaccine-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

E) the need to cook all such plants before consuming them

A

Pharmacogenetics is an increasingly important discipline that uses genetic information to tailor the prescription of drug treatments to individuals. In the case of chemotherapy for breast cancer, for example, different patients need and/or respond to different treatments.

63) Patients whose tumors are HER-2 positive respond to herceptin whereas other patients do not. Patients whose tumors have estrogen receptors will be best served if

A) their estrogen receptors are blocked by using RNAi.

B) their estrogen release is activated and/or elevated.

C) the estrogen receptors are blocked by other molecules that can use the same receptors.

D) they are given herceptin as well as estrogen.

E) they are given a complete hysterectomy.

C

Pharmacogenetics is an increasingly important discipline that uses genetic information to tailor the prescription of drug treatments to individuals. In the case of chemotherapy for breast cancer, for example, different patients need and/or respond to different treatments.

64) Breast tumor biopsy specimens can be typed for a number of gene expression patterns. Together, these can provide risk analysis for the likely aggressive growth and metastasis of the tumor. How can this most help the physician and patient?

A) Some patients want to know as much as possible.

B) This can help them to decide whether and what kind of chemotherapy is warranted.

C) This can help them decide whether the tumor should be removed.

D) Some physicians may use the information to decide what to do, but not tell the patient.

E) This can help to aggregate health statistics.

B

7) Why is it so important to be able to amplify DNA fragments when studying genes?
A) Before amplification, DNA fragments are likely to bind to RNA and no longer be able to be analyzed.
B) A gene may represent only a millionth of the cell's DNA.
C) Restriction enzymes (endonucleases) cut DNA into fragments that are too small.
D) A clone requires multiple copies of each gene per clone.

B

9) The reason for using Taq polymerase for PCR is that _____.

A) it is heat stable and can withstand the heating step of PCR

B) only minute amounts are needed for each cycle of PCR
C) it binds more readily than other polymerases to the primers

D) it has regions that are complementary to the primers

A

15) What information is critical to the success of polymerase chain reaction (PCR) itself?

A) The DNA sequence of the ends of the DNA to be amplified must be known.
B) The complete DNA sequence of the DNA to be amplified must be known.
C) The sequence of restriction-enzyme recognition sites in the DNA to be amplified must be known.

D) The sequence of restriction-enzyme recognition sites in the DNA to be amplified and in the plasmid where the amplified DNA fragment will be cloned must be known.

A

16) Which of the following is in the correct order for one cycle of polymerase chain reaction (PCR)?
A) Denature DNA; add fresh enzyme; anneal primers; add dNTPs; extend primers.
B) Anneal primers; denature DNA; extend primers.

C) Extend primers; anneal primers; denature DNA.

D) Denature DNA; anneal primers; extend primers.

D

17) The final step in a Sanger DNA sequencing reaction is to run the DNA fragments on a gel. What purpose does this serve?
A) It adds ddNTP to the end of each DNA fragment.
B) It changes the length of the DNA fragments.

C) It separates DNA fragments based on their charge.
D) It separates DNA fragments generated during the sequencing reaction based on one- nucleotide differences in their size.

D

18) DNA sequencing has transformed our understanding of genes, genomes and evolution. Which of the following statements comparing two common sequencing techniques, the chain termination method and next generation sequencing is TRUE?
A) The chain termination method is faster and more efficient, so it is used to generate large-scale sequences, while next generation synthesis is used for routine, small-scale jobs.

B) The chain termination method employs the polymerase chain reaction, but next generation sequencing does not.
C) In the chain termination method, the order of bases is detected by fluorescently labeling each dideoxy-nucleotide in a different color, while next generation sequencing determines the order of bases by detecting the release of PPi during the formation of the phosphodiester bond.

D) Next generation sequencing employs electrophoresis, but the chain termination method does not

C

19) A gene that contains introns can be made shorter (but remain functional) for genetic engineering purposes by using _____.
A) a restriction enzyme (endonuclease) to cut the gene into shorter pieces
B) reverse transcriptase to reconstruct the gene from its mRNA

C) DNA polymerase to reconstruct the gene from its polypeptide product
D) DNA ligase to put together fragments of the DNA that code for a particular polypeptide

B

22) RNAi methodology uses double-stranded pieces of RNA to trigger breakdown of a specific mRNA or inhibit its translation. For which of the following might this technique be useful?
A) to decrease the production from a harmful mutated gene
B) to destroy an unwanted allele in a homozygous individual

C) to form a knockout organism that will not pass the deleted sequence to its progeny

D) to raise the concentration of a desired protein

A

27) Imagine that you compare two DNA sequences found in the same location on homologous chromosomes. On one of the homologs, the sequence is AACTACGA. On the other homolog, the sequence is AACTTCGA. Within a population, you discover that each of these sequences is common. These sequences _____.

A) contain an SNP that may be useful for genetic mapping

B) identify a protein-coding region of a gene
C) cause disease
D) do none of the listed actions

A

28) Which of the following uses labeled probes to visualize the expression of genes in whole tissues and organisms?
A) RT-PCR
B) in situ hybridization

C) DNA microarrays
D) RNA interference

B

34) A researcher is using adult stem cells and comparing them to other adult cells from the same tissue. Which of the following is a likely finding?
A) The cells from the two sources exhibit different patterns of DNA methylation.
B) Adult stem cells have more DNA nucleotides than their counterparts.

C) The two kinds of cells have virtually identical gene expression patterns in microarrays.

D) The nonstem cells have fewer repressed genes.

A

41) Which of the following is one of the technical reasons why gene therapy is problematic?

A) Most cells with an engineered gene do not produce gene product.
B) Cells with transferred genes are unlikely to replicate.
C) Transferred genes may not have appropriately controlled activity.

D) mRNA from transferred genes cannot be translated.

C

43) What characteristic of short tandem repeats (STRs) DNA makes it useful for DNA fingerprinting?
A) The number of repeats varies widely from person to person or animal to animal.
B) The sequence of DNA that is repeated varies significantly from individual to individual.

C) The sequence variation is acted upon differently by natural selection in different environments.

D) Every racial and ethnic group has inherited different short tandem repeats.

A

45) Gene therapy requires _____.
A) knowledge and availability of the normal allele of the defective gene
B) the ability to introduce the normal allele into the patient
C) the ability to express the introduced gene at the correct level, time, and tissue site within the patient
D) knowledge and availability of the normal allele of the defective gene, an ability to introduce the normal allele into the patient, and an ability to express the introduced gene at the correct level, and time, and tissue site within the patient

D

46) For applications in gene therapy, what is the most favorable characteristic of retroviruses?

A) Retroviruses have an RNA genome.
B) Retroviruses possess reverse transcriptase.
C) DNA copies of retroviral genomes become integrated into the genome of the infected cell. D) Retroviruses mutate often.

C

47) Using retroviral vectors for gene therapy might increase the patient's risk of developing cancer because they might _____.
A) introduce proteins from the virus
B) not express the genes that were introduced into a patient's cells

C) not integrate their recombinant DNA into the patient's genome
D) integrate recombinant DNA into the genome in ways that misregulate the expression of genes at or near the site of integration

D

9) One predicted aspect of climate change is that climates, including precipitation and temperature, over most of the Earth will become more variable. Which of the following is a good crop genetic engineering strategy if this is true?
A) Only plant crops that are genetically engineered.
B) Genetically engineer most crops to withstand very long droughts.
C) Genetically engineer several genotypes within single crop types.
D) Genetically engineer the fastest growing crops possible.

C

50) Plasmids are used as vectors in plant and bacterial genetic engineering. However, there is a major difference in the fate of genes introduced into bacteria on most bacterial plasmids and into plants on tumor-inducing (Ti) plasmids. What is this difference?
A) In bacteria, genes are stably expressed; in plants, gene expression is always lost quickly.

B) Gene expression tends to decrease rapidly and unpredictably in bacteria; gene expression is much more stable in plants.
C) Bacterial plasmids are circular DNAs; Ti plasmid DNA is linear.
D) Bacterial plasmids and the genes they carry usually are not integrated into the chromosome; Ti plasmids and the genes they carry are integrated into the chromosome

D

51) In an experiment, DNA from the linear form of the bacteriophage Lambda was cut into fragments using the restriction enzyme Hind III. Restriction enzymes are isolated from bacteria and cut DNA in specific locations. Hind III cuts the Lambda DNA between the adenine nucleotides on the complimentary strands in a specific sequence, as indicated in the diagram, producing eight different size fragments. These fragments are then separated with an electrical current based on size after the DNA fragments are placed in a porous gel, a process called gel electrophoresis.

Select an observation that best describes a correct aspect of the two processes of restriction digest and gel electrophoresis:
A) When separated on a gel, the pattern of DNA bands will be characteristic of those cut with Hind III, different restriction enzymes will not produce these same fragments.

B) The sequence AAGCTT is found eight times in the Lambda genome and the restriction enzyme Hind III finds each location.
C) If an electrical current is not used, eight separate DNA bands would be visible, but they would not be separated as much as when an electrical current is used.

D) Only the restriction enzyme Hind III can be used to cut Lambda DNA since restriction enzymes are specific to the type of DNA they can cut.

A

52) Organisms share many conserved core processes and features, including transcription and translation using a uniform genetic code. Scientists have used these shared processes and features in biotechnology. For example, for the process of some transformations, a plasmid is constructed when a eukaryotic gene of interest is added with an antibiotic resistant gene such beta-lactamase, which is used for ampicillin resistance. This plasmid is then inserted into a prokaryotic bacterial cell, such as E-coli, through a transformation process that leads to the production of the product protein from the eukaryotic organism. To culture the bacteria and obtain the protein product, the bacteria must grow.

Select the appropriate condition to determine if the plasmid has entered the E-coli bacterial cell. A) Nutrient broth to which no antibiotic has been added.
B) Water to which ampicillin has been added.
C) Nutrient broth to which ampicillin has been added.

D) Nutrient broth to which other resistant bacteria have been added.

C