Deck 18: Dna Technology: Making and Using Genetically Altered Organisms, and Other Applications

Question 1

The DNA sequence recognized by restriction endonucleases is generally ____ base pairs long.

A) 1-2
B) 4-8
C) 10-15
D) 24-32
E) 36-47

Answer 1

B

Question 2

In which situation would gene cloning occur?

A) A DNA fragment is inserted directly into a bacterium and is replicated.
B) A DNA fragment is inserted into a plasmid, which is then introduced into a bacterium where the gene is expressed, but the plasmid does not replicate.
C) A DNA fragment is inserted into a plasmid, which is then introduced to a bacterium where the plasmid replicates.
D) A DNA fragment is inserted directly into a bacterium and is digested by nucleases.
E) A protein of interest is taken up by a bacterium, which incorporates the protein into its cell membrane.

Answer 2

C

Question 3

When cloning DNA into bacteria, the ____.

A) DNA sequence is inserted into a plasmid
B) DNA sequence is inserted into the bacterial chromosome
C) linear DNA sequence is circularized, thus generating a plasmid
D) new DNA is directly introduced into the bacterial cell
E) approach depends on the species of host bacteria used in the experiment

Answer 3

A

Question 4

The characterization of whole genomes, including their structures (sequences), functions, and evolution is called ____.

A) genetic engineering
B) genomics
C) bioinformatics
D) biotechnology
E) genetic engineering

Question 5

Plasmids are ____.

A) enzymes that cut DNA
B) RNA molecules
C) small proteins that help replicate cloned genes
D) protein-coding genes in the chromosome
E) circular DNA molecules that replicate separately from chromosomal DNA

Question 6

Bioinformatics combines the fields of ____ to extract information from biological data.

A) computer science and social science
B) mathematics and social science
C) mathematics and computer science
D) biology and history
E) biology and physics

Question 7

Genetically altered organisms are ____.

A) always genetically modified organisms
B) always made using DNA technologies
C) only used in basic research
D) only used in applied research
E) created through natural mutations or by using DNA technologies

Question 8

DNA is cut by ____.

A) nucleases
B) proteases
C) stem cells
D) Ti plasmids
E) restriction fragment length polymorphisms

Question 9

Copies of recombinant DNA are produced in a genetically engineered organism by ____.

A) reverse transcriptase
B) exonucleases
C) restriction endonucleases
D) DNA ligase
E) DNA polymerase

Question 10

A researcher wants to insert a DNA fragment into a plasmid. Which enzyme will join the two DNA molecules together?

A) primase
B) β-galactosidase
C) restriction endonuclease
D) DNA ligase
E) DNA polymerase

Question 11

What is the natural function of restriction endonucleases?

A) research applications
B) DNA manipulation in vitro
C) defense against viruses that infect bacteria
D) regulating bacterial gene expression
E) breaking phosphodiester bonds in mammalian DNA

Question 12

If a restriction endonuclease cuts a linear DNA three times, how many fragments should there be after the DNA is subjected to electrophoresis through an agarose gel?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 13

Some restriction endonucleases cut DNA in such a way that short, single-stranded regions known as ____ ends are created.

A) hydrogen-bonding
B) sticky
C) tacky
D) blunt
E) jagged

Question 14

Most genetic alterations performed by researchers aim to change the ____.

A) genotype of the organism without a change in phenotype
B) genotype of the organism, causing a change in phenotype
C) phenotype of the organism without a change in genotype
D) phenotype of the organism, causing a change in genotype
E) proteome of the organism without a change in genotype

Question 15

When the sequence of nucleotides read in the 5 ¢® 3 ¢ direction on one strand is same as the sequence read in the 5 ¢® 3 ¢ direction on the complementary strand, the sequence is called a(n) ____.

A) inverted sequence
B) palindrome
C) restriction site
D) restriction fragment length polymorphism
E) inactive restriction site

Question 16

Recombinant DNA is ____.

A) DNA encoding restriction endonucleases
B) a gene of interest found in the genome
C) DNA fragments from the same organism that have been joined together to form a single molecule
D) DNA fragments from two or more different sources that have been joined together to form a single molecule
E) a plasmid containing DNA from a single source

Question 17

Restriction endonucleases break ____ bonds.

A) phosphodiester
B) ester
C) glycosidic
D) peptide
E) hydrogen

Question 18

An organism whose genome has been modified to change a genetic trait or traits by using traditional breeding techniques, classical genetic approaches, or modern molecular manipulation techniques is called a ____.

A) bacterium
B) clone
C) transcriptionally modified organism
D) genetically altered organism
E) somatic organism

Question 19

Bacteria protect restriction sites in their own DNA from being cut by restriction enzymes by ____.

A) synthesizing low quantities of restriction enzymes
B) producing restriction enzymes that do not recognize sequences in their own DNA
C) chemically modifying bases within the restriction sites
D) only activating restriction enzymes when foreign DNA is present in the cell
E) inactivating restriction enzymes through phosphorylation

Question 20

If a restriction endonuclease cuts a circular DNA three times, how many fragments should there be after the DNA is subjected to electrophoresis through an agarose gel?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 21

A plasmid cloning vector and DNA fragments containing the XYZ gene, each digested with the same restriction enzyme, are mixed with DNA ligase. Which product(s) will result?

A) Recombinant plasmids only
B) Nonrecombinant plasmids only
C) Joined-together copies of the DNA fragment containing the XYZ gene only
D) A mixture of recombinant plasmids, nonrecombinant plasmids, and joined-together copies of the DNA fragment containing the XYZ gene
E) No reaction will occur because DNA polymerase, rather than DNA ligase, is needed to insert the DNA fragments into the plasmid cloning vector

Question 22

Which component of the PCR reaction is responsible for its specificity?

A) the pair of DNA primers
B) the pair of RNA primers
C) DNA polymerase
D) the four nucleoside triphosphates
E) the thermocycler

Question 23

Bacteria transformed with plasmids are plated on growth medium containing ampicillin and X-gal. White colonies on the plate contain bacteria with a ____ plasmid, meaning the lacZ⁺gene is ____.

A) recombinant; deleted from the plasmid
B) nonrecombinant; intact
C) recombinant; intact
D) nonrecombinant; disrupted by the inserted DNA fragment
E) recombinant; disrupted by the inserted DNA fragment

Question 24

Why is it important to have an antibiotic resistance gene in plasmid cloning vectors?

A) It helps the host bacteria grow faster.
B) It allows researchers to distinguish bacteria that contain the plasmid from those that do not.
C) It aids scientists in developing new antibiotic treatments.
D) It allows researchers to distinguish bacteria that contain the recombinant vector from those that contain just the vector.
E) It helps the bacteria replicate the recombinant plasmid more quickly.

Question 25

40. Identify the correct steps for cloning a gene of interest, then arrange them in the correct order. One of the steps below is left out of the answer. 1. Transform the bacteria.
2) Incubate the DNA fragments and cut cloning vector with DNA ligase.
3) Use restriction enzymes to cut the gene of interest and the cloning vector.
4) Spread bacteria on medium containing lactose and ampicillin.
5) Spread bacteria on medium containing X-gal and ampicillin.

A) 4, 3, 1, 5
B) 3, 2, 5, 1
C) 3, 2, 1, 5
D) 2, 3, 1, 5
E) 3, 2, 1, 4

Question 26

Plasmid cloning vectors generally contain genes for which two traits?

A) lacA production and ampicillin resistance
B) β-galactosidase enzyme production and ampicillin resistance
C) DNA ligase production and sticky ends
D) DNA ligase and reverse transcriptase production
E) DNA polymerase production and antibiotic resistance

Question 27

β-galactosidase is used in bacterial screening assays for visualization of colonies that contain recombinant DNA. What is its substrate?

A) lactose
B) X-gal
C) sucrose
D) lacZ
E) agarose

Question 28

What enables a PCR-amplified gene to be inserted into a cloning vector?

A) The PCR reaction adds sticky ends onto the amplified DNA, allowing ligation to a cloning vector.
B) Restriction enzyme sites are added to the 5 ¢ ends of both primers; therefore, digestion of the PCR-amplified gene allows ligation to a cloning vector cut with the same restriction enzyme.
C) The PCR-amplified gene is sequenced to locate restriction sites in order to determine which restriction enzymes to use for cloning.
D) The PCR-amplified gene is cut with one restriction enzyme, then ligated to a cloning vector cut by a different restriction enzyme.
E) The cloning vector is added to the PCR reaction, and once the gene is amplified, it immediately ligates to the cloning vector.

Question 29

The phases of each PCR cycle listed in order are ____.

A) denaturation, extension, and annealing
B) annealing, extension, and denaturation
C) extension, denaturation, and annealing
D) annealing, denaturation, and extension
E) denaturation, annealing, and extension

Question 30

How is a DNA fragment containing a gene of interest generated for cloning?

A) The gene with a cloning vector is ligated.
B) Agarose gel electrophoresis takes place.
C) The polymerase chain reaction (PCR) amplifies the DNA fragment from the genome.
D) A DNA polymerase specific for the fragment is used to make copies.
E) DNA fingerprinting allows the fragment to be copied from the chromosome.

Question 31

During DNA cloning, why is the DNA of interest inserted into the middle of the lacZ⁺coding sequence in the plasmid vector?

A) It makes the bacteria resistant to the antibiotic.
B) It allows researchers to distinguish bacteria that contain the plasmid from those that do not.
C) It aids scientists in developing new antibiotic treatments.
D) It allows researchers to distinguish bacteria that contain the recombinant plasmid from those that contain just the vector.
E) It makes the bacteria produce more clones.

Question 32

Which feature of a plasmid cloning vector is necessary for the plasmid to be replicated inside a host cell?

A) lacZ⁺gene
B) ampicillin resistance gene
C) origin of replication
D) ribosomal binding site
E) restriction site

Question 33

The key elements of a PCR reaction are ____.

A) the four nucleoside triphosphates, DNA primase, DNA polymerase, and an agarose gel
B) a pair of primers, the four nucleoside triphosphates, DNA primase, and DNA polymerase
C) DNA with the target sequence to be amplified, the four nucleoside triphosphates, DNA primase, and DNA polymerase
D) DNA with the target sequence to be amplified, a pair of primers, the four nucleoside triphosphates, and DNA primase
E) DNA with the target sequence to be amplified, a pair of primers, the four nucleoside triphosphates, and DNA polymerase

Question 34

Bacteria transformed with plasmids are plated on growth medium containing ampicillin and X-gal. Blue colonies on the plate contain bacteria with a ____ plasmid, meaning the lacZ⁺gene is ____.

A) recombinant; deleted from the plasmid
B) nonrecombinant; intact
C) recombinant; intact
D) nonrecombinant; disrupted by the inserted DNA fragment
E) recombinant; disrupted by the inserted DNA fragment

Question 35

How do scientists determine the annealing temperature used in PCR reactions?

A) It is always 55^ᵒC because the DNA polymerase works best at this temperature.
B) It is always 55^ᵒC because primers anneal best at lower temperatures.
C) It is always 65^ᵒC because any other temperature would destabilize the DNA.
D) It can vary from 55-65^ᵒC depending on the primers being used.
E) It can vary from 55-65^ᵒC depending on the type of DNA polymerase being used.

Question 36

PCR is ____.

A) repeated DNA replication cycles of a specific region of a DNA molecule
B) DNA replication in which DNA polymerase replicates an entire chromosome
C) a reaction in which restriction enzymes cut a gene of interest from the chromosome
D) transcription during which only a portion of the cell's DNA is expressed
E) translation during which only some mRNA molecules are translated to make proteins

Question 37

When DNA fragments are sealed together by DNA ligase, the process is referred to as ____.

A) transformation
B) gene remodeling
C) the polymerase chain reaction
D) restriction cloning
E) ligation

Question 38

I need to determine if the gene for a particular protein is the same length in frogs, humans, and trees. Which method(s) will be most helpful to me?

A) PCR and agarose gel electrophoresis
B) DNA cloning and PCR
C) DNA cloning only
D) PCR only
E) agarose gel electrophoresis only

Question 39

Mass quantities of a target DNA sequence can be obtained by ____.

A) restriction endonuclease digestion only
B) gene cloning only
C) PCR only
D) restriction endonuclease digestion and PCR
E) gene cloning and PCR

Question 40

Taq polymerase is commonly used in PCR reactions because it ____.

A) keeps the primers from annealing to the DNA
B) makes fewer DNA replication errors than other DNA polymerases
C) is a heat-stable DNA polymerase
D) is more efficient at replicating DNA than other DNA polymerases
E) helps the primers anneal to the correct DNA sequence

Question 41

Reverse-transcriptase PCR ____.

A) uses Taq polymerase to produce cDNA copies of RNA transcripts
B) uses RNA polymerase to amplify cDNA copies of RNA transcripts
C) uses RNA polymerase to produce mRNA copies of a gene
D) amplifies cDNA copies of RNA transcripts
E) uses reverse transcriptase to produce mRNA copies of a gene

Question 42

An example of pharming is ____.

A) photosynthetic bacteria that clean up oil spills
B) transgenic sheep that produce a protein required for normal blood clotting in humans
C) E. coli that synthesize restriction enzymes for use in genetic engineering
D) yeast that produce ethanol for use as fuel in vehicles
E) a genetically modified crop plant that is resistant to pesticide

Question 43

In agarose gel electrophoresis, DNA molecules move toward the ____ pole because they ____.

A) positive; are negatively charged
B) negative; are positively charged
C) bottom; are pulled by a magnetic force
D) bottom; are pulled by gravity
E) bottom; have a greater density than the gel

Question 44

Agarose gel electrophoresis separates DNA molecules according to their ____.

A) charge
B) length
C) sequence
D) percentage of GC base pairs
E) structure

Question 45

What molecular tool has applications like correcting gene mutations, creating specific mutations, knocking out genes, inserting genes, engineering animals for use in human organ transplants, engineering crops and livestock to improve yields, and developing animal models of human genetic diseases?

A) agarose gel electrophoresis
B) the CRISPR-Cas9 system
C) gene targeting
D) DNA cloning
E) polymerase chain reaction (PCR)

Question 46

The enzyme ____ produces ____ DNA that is complementary to mRNA.

A) reverse transcriptase; single-stranded
B) reverse transcriptase; double-stranded
C) DNA polymerase; single-stranded
D) DNA polymerase; double-stranded
E) RNA polymerase; single-stranded

Question 47

The protein-coding region of a eukaryotic gene ____.

A) can be amplified directly from the genome
B) is obtained by producing a cDNA copy from the gene's transcript
C) contains introns, so an mRNA copy must be produced from the gene's transcript
D) contains exons that are removed by restriction enzymes, while the remaining introns are ligated together
E) contains introns that are removed by restriction enzymes, while the remaining exons are ligated together

Question 48

Organisms that have been genetically engineered are called ____, because they have been modified to contain genetic information called a(n) ____ from an external source.

A) transgenic; transgene
B) transgenic; oncogene
C) somatic; Ti plasmid
D) genetically modified organisms; restriction fragment length polymorphism
E) somatic; transgene

Question 49

The CRISPR-Cas9 system is exploited experimentally for ____.

A) programmable RNA-guided genome editing
B) programmable DNA-guided genome editing
C) cutting DNA at specific sites so it can be inserted into a cloning vector
D) increasing transcription of a gene of interest
E) enhancing DNA polymerase activity in PCR reactions

Question 50

The technique by which DNA, RNA, or protein molecules are separated in a gel that is subjected to an electric field is called ____.

A) PCR
B) biotechnology
C) amplification
D) a restriction enzyme digestion
E) gel electrophoresis

Question 51

Figure 18.1 (questions 44-47)
Answer the question using the accompanying figure. Of the fragments labeled A-D, which is the smallest?

A) A
B) B
C) C
D) D
E) it is impossible to tell

Question 52

What distinguishes expression vectors from other cloning vectors?

A) Expression vectors do not have an origin of replication.
B) Only expression vectors have origins of replication.
C) Expression vectors contain regulatory sequences to allow transcription and translation of an inserted gene.
D) Inserted genes cannot be transcribed from an expression vector.
E) Expression vectors do not contain antibiotic resistance genes.

Question 53

All stem cells ____.

A) are differentiated cells that proliferate indefinitely
B) can differentiate into any cell type, but can only divide once after terminally differentiating
C) have the ability to differentiate into all cell types
D) are undifferentiated cells that proliferate indefinitely
E) are undifferentiated cells that proliferate a finite number of times

Question 54

Why are numerous replication cycles - each performed at three difference temperatures - a necessary part of a PCR reaction?

A) The initial cycles do not produce many copies of the target sequence, but since the number of molecules produced doubles with each cycle, millions of copies are produced after 20-30 cycles.
B) The initial cycles amplify DNA slowly, but as the temperature increases, DNA polymerase works more quickly to produce millions of copies of the target sequence.
C) The bacteria used in the reaction divide with each cycle, replicating the target DNA.
D) Only non-target DNA is made during the first 10 cycles, while only cycles 11-20 specifically target the gene of interest.
E) Once the enzyme starts working, it must continue until there are no remaining nucleotides.

Question 55

Figure 18.1 (questions 44-47)
Answer the question using the accompanying figure. What does letter E represent?

A) different RNA molecules transcribed from a coding region of DNA
B) the products of a PCR reaction in which the primers annealed to multiple sites
C) the products of a PCR reaction performed without one of the nucleoside triphosphates
D) the products of a PCR reaction that had more than two primers
E) a DNA marker ladder

Question 56

A researcher is interested in studying gene X, but not gene Y, in Drosophila . What does she need to amplify only gene X from the Drosophila genome?

A) some prior knowledge of the gene X sequence so that appropriate primers can be designed
B) a heat-stable restriction endonuclease
C) restriction endonucleases that cut gene X, but not gene Y
D) a cloning vector that has multiple antibiotic resistance genes
E) a cloning vector that will ligate to gene X, but not to gene Y

Question 57

What is the main difference between germline gene therapy and somatic gene therapy?

A) Only somatic gene therapy can result in the modified genes being passed to the next generation.
B) The effects of germline gene therapy are limited to the current generation.
C) In germline gene therapy, the gametes are altered; in somatic gene therapy, body cells affected by a genetic disorder are altered.
D) In somatic gene therapy, the gametes are altered; in germline gene therapy, only the body cells are altered.
E) Only germline gene therapy is ethical for research purposes in rodents

Question 58

Figure 18.1 (questions 44-47)
Answer the question using the accompanying figure. Of the fragments labeled A-D, which is closest to the negative electrode?

A) A
B) B
C) C
D) D
E) They are all the same distance from the negative electrode.

Question 59

In agarose gel electrophoresis, DNA is visualized by ____.

A) staining the gel with an agarose-binding dye so the gel, but not the DNA bands, fluoresces under UV light
B) staining the DNA with a DNA-binding dye that fluoresces under natural light
C) staining the DNA with X-gal so that the DNA bands appear blue
D) staining the gel with a DNA-binding dye that fluoresces under UV light
E) staining the gel with a DNA-binding dye that fluoresces under natural light

Question 60

Figure 18.1 (questions 44-47)
Answer the question using the accompanying figure. Of the fragments labeled A-D, which is closest to the positive electrode?

A) A
B) B
C) C
D) D
E) It is impossible to tell.

Question 62

Figure 18.2 (question 74)
Answer the question using the accompanying figure. The figure shows the alleles present at an STR locus in two adults and four juveniles. Which of the juvenile(s) could be offspring of the adults?

A) juvenile 2 only
B) juveniles 2 and 3
C) juveniles 1 and 4
D) juveniles 2 and 4
E) juveniles 1, 2, 3, and 4

Question 63

Crops that are resistant to the herbicide Roundup ____.

A) express the enzyme degraded by Roundup at high levels so that not all of the enzyme is inhibited
B) have an extra coating outside their cell wall that inhibits Roundup from entering the cells
C) contain a bacterial version of the chloroplast enzyme inhibited by Roundup
D) produce a compound that degrades Roundup
E) do not have the membrane channels through which Roundup enters the plant

Question 64

Gel electrophoresis can only be used to analyze DNA samples.

Question 65

Define the purpose of inserting a gene into a plasmid cloning vector.

Question 66

In standardized DNA fingerprinting used in the United States, ____.

A) 20 different noncoding loci are examined
B) 20 different coding loci are examined
C) only loci that do not vary among individuals are examined
D) only long tandem repeats loci are examined
E) the sequence of short tandem repeats is determined

Question 67

The Ti plasmid is used to ____.

A) create clones of mammals
B) treat human diseases by somatic gene therapy
C) insert transgenes into bacteria
D) insert transgenes into plants
E) insert transgenes into animals

Question 68

Transgenic organisms contain extra copies of their own genes.

Question 69

The vectors used in somatic gene therapy are mostly _____.

A) bacterial plasmids
B) eukaryotic plasmids
C) retroviruses or inactivated viruses
D) DNA viruses and reactivated viruses
E) naked genes

Question 70

Restriction fragment length polymorphisms (RFLPs) are used to ____.

A) test the effectiveness of different restriction enzymes on a sequence of DNA
B) compare the DNA sequences between individuals by looking for changes in restriction enzyme digest patterns
C) compare the full DNA sequences of two individuals
D) prepare DNA for further sequence analysis
E) treat sickle-cell anemia

Question 71

Explain the ethical concerns with germline gene therapy in humans.

Question 72

Restriction enzyme-generated DNA fragments of different lengths from the same region of the genome are called ____.

A) DNA elements
B) endonuclease sites
C) restriction sites
D) restriction fragment length polymorphisms
E) restriction elements

Question 73

Which statement is accurate regarding DNA technologies?

A) Humans have been successfully cloned.
B) Germline gene therapy is used to treat genetic conditions in humans.
C) Genetically engineered microorganisms constitute a large public concern.
D) Possible problems associated with GMOs are a public concern.
E) Bacterial cloning and animal cloning follow largely similar techniques.

Question 74

Which statement correctly describes single-nucleotide polymorphisms (SNPs)?

A) A SNP locus typically has more than two alleles.
B) SNPs are typically used as markers of a region of the genome.
C) The frequency of the rarer SNP allele must be less than 1%.
D) SNPs are the least common form of human genetic variation.
E) If only two alleles are associated with a SNP, both must have relatively the same frequency in the population.

Question 75

In sickle cell anemia, a ____ mutation in the β-globin gene eliminates a ____.

A) single base-pair; restriction site
B) frameshift; restriction site
C) nonsense; promoter region
D) single base-pair; promoter region
E) nonsense; restriction site

Question 76

How is DNA introduced into plants using the Ti plasmid?

A) The gene of interest remains in the Ti plasmid after the plasmid has transformed the plant, and the gene is expressed in the plant.
B) The Ti plasmid inserts the gene of interest directly into the plant's nuclear DNA.
C) The entire Ti plasmid including the gene of interest is inserted into the plant's nuclear DNA.
D) The Ti plasmid inserts the foreign DNA into the plant's chloroplast DNA.
E) The Ti plasmid inserts the foreign DNA into the plant's mitochondrial DNA.

Question 77

What is a GMO? What are the potential concerns and benefits associated with GMOs?

Question 78

What is another name for a short tandem repeat (STR) sequence?

A) minisatellite
B) microsatellite
C) microRNAs (miRNAs)
D) STDs
E) lncRNAs

Question 79

DNA fingerprinting is a method used to ____.

A) identify a species
B) distinguish between two individuals of the same species
C) examine the DNA sequences encoding for human fingerprints
D) extract DNA samples from human fingerprints
E) determine the sequence of the human genome

Question 80

Why was the nucleus removed from the egg cell used to create Dolly, the cloned sheep?

A) to remove the mitochondrial DNA of the egg donor
B) to test whether the genetic contribution from a sperm cell alone could produce a lamb
C) to create a cloned sheep in the absence of DNA
D) since the genome for the clone was supplied by the diploid mammary cell, the presence of the egg cell DNA would result in triploidy
E) to see whether egg cell DNA injected into a sperm cell could produce a lamb