micro - mastering assignment 8
A source of heat-stable DNA polymerase is Bacillus thuringiensis. Saccharomyces cerevisiae. Agrobacterium tumefaciens. Thermus aquaticus. Pseudomonas.
Thermus aquaticus.
A new arrow labeled "lengthens" could be added between __________. "target DNA" → "DNA strands" "primers" → "DNA strands" "target DNA" → "primers" "Taq polymerase" → "primers"
"Taq polymerase" → "primers
What provides the energy for DNA polymerization in a PCR reaction? Deoxyribonucleoside triphosphates Primers DNA polymerase Template DNA
Deoxyribonucleoside triphosphates
Which of the following places the steps in the PCR procedure in the correct order? 1) Incubate at 94°C to denature DNA strands; 2) Incubate at 72°C for DNA synthesis; 3) Incubate at 60°C for primer hybridization. 3, 2, 1 1, 3, 2 3; 1; 2 1, 2, 3 2; 1; 3
1, 3, 2
In which direction does DNA polymerase synthesize the new DNA strand? 3' to 5' 5' to 3' Both 5' to 3' and 3' to 5'
5' to 3'
What is the temperature used for the extension step? 72 °C 60 °C 94 °C
72 °C
What is the sequence of the temperatures of a typical PCR reaction? 94 °C, 60 °C, 72 °C 72 °C, 94 °C, 60 °C 94 °C, 72 °C, 60 °C 72 °C, 60 °C, 94 °C 60 °C, 72 °C, 94 °C
94 °C, 60 °C, 72 °C
The Pap test for cervical cancer involves microscopic examination of cervical cells for cancerous cells. A new, rapid diagnostic test to detect human papilloma virus (HPV) DNA before cancer develops is done without microscopic exam. The steps involved in this FastHPV test are listed below. What is the second step? The order is unimportant. Add enzyme substrate. Add enzyme-linked antibodies against DNA-RNA. Add an RNA probe for HPV DNA. Lyse human cells.
Add an RNA probe for HPV DNA.
Which of the following best describes how recombinant DNA technology currently helps patients who do NOT produce adequate amounts of growth hormone (hGH)—a condition that otherwise leads to stunted growth? Recombinant vectors are used to stimulate hGH production in these patients. Recombinant vectors now produce hGH. Bacteria now produce hGH. Bacteria now produce rDNA coding for hGH.
Bacteria now produce hGH.
Which of the following best describes why a vector is used in genetic modification procedures? Cells usually won't copy an isolated gene sequence. The gene of interest must be isolated from adjacent genes. The vector ensures that the clone remains pure. The clone must be able to produce proteins from the rDNA containing the gene of interest.
Cells usually won't copy an isolated gene sequence.
Which of the following methods could be used to identify the source of an outbreak? production of a recombinant protein reverse genetics DNA fingerprinting artificial selection
DNA fingerprinting
Which of the following attaches the target gene to a desired location? Restriction enzymes Plasmids Chromosomal DNA DNA ligase
DNA ligase
Which enzyme would cut this strand of DNA? GCATGGATCCCAATGC Enzyme Recognition EcoRI GAATTC CTTAAG Enzyme Recognition HaeIII GGCC CCGG Enzyme Recognition BamHI GGATCC CCCTAGG Enzyme Recognition Pst ICTGCG GACGTC Enzyme Recognition HindIII AAGCTT TTCGAA
Enzyme Recognition BamHI GGATCC CCCTAGG
Nearly all cells, including E. coli and yeast, naturally take up DNA from their surroundings without chemical treatment. True False
False
The term biotechnology refers exclusively to the use of genetically engineered organisms for the production of desired products. True False
False
Bt crops, including potatoes and cotton, are genetically engineered using laboratory techniques. Which of the following utilizes recombinant DNA technology to produce advantageous traits in the crops that are produced? Genetically engineered crops have natural characteristics that give them a genetic advantage. Genetically engineered crops have a genetic advantage because the parent strains have advantageous traits. Genetically engineered crops have an advantageous gene from another organism inserted into their genome. Genetically engineered crops naturally produce larger plants and bountiful products
Genetically engineered crops have an advantageous gene from another organism inserted into their genome.
Bt crops are engineered in the lab to produce Bt toxins due to the presence of a bacterial gene from B. thuringiensis. Why is it advantageous for the plants to produce the Bt toxin? The Bt toxin will protect the plant from pathogenic bacteria. The plant will release chemicals that will repel all nearby insects. People who eat the food produced by a Bt crop will be resistant to bacterial infections. Insects that normally destroy non-toxin-producing crops will be killed when they eat plants that do produce the toxin.
Insects that normally destroy non-toxin-producing crops will be killed when they eat plants that do produce the toxin.v
Why would a recombinant DNA molecule be inserted into a host cell? Restriction enzymes can only be used inside of a cell. It can protect the recombinant DNA. Plasmids cannot be isolated outside of a host cell. It can be copied, transcribed, and translated into a desired protein.
It can be copied, transcribed, and translated into a desired protein.
Why is DNA polymerase from Thermus aquaticus ideal for PCR? It does not require primers. It can withstand the high temperatures associated with PCR. It does not require energy to polymerize DNA. It can synthesize DNA 5' to 3' and 3' to 5'.
It can withstand the high temperatures associated with PCR.
Which of the following is an advantage of using E. coli to make a human gene product? It cannot process introns. Its genes are well known. It does not secrete most proteins. Endotoxin may be in the product. Endotoxin may be in the product and it does not secrete most proteins.
Its genes are well known.
Recombinant DNA techniques typically involve generating a clone. Why? Recombining the clone produces the recombinant DNA. Producing a clone generates many copies of the gene of interest. A clone is generated when a cell takes up the vector. A clone is used to get the gene of interest into a suitable cell.
Producing a clone generates many copies of the gene of interest.
Which of the following is an application that uses PCR? Diagnosing a disease Sequencing a gene Sequencing a gene, diagnosing a disease, and providing enough DNA for cloning into another organism Providing enough DNA for cloning into another organism
Sequencing a gene, diagnosing a disease, and providing enough DNA for cloning into another organism
Which of the following best explains how scientists are able to introduce the bacterial gene for Bt toxin into the cotton plant genome? The bacterial gene for Bt toxin is isolated, and the DNA is put into tiny bullets (like BB's) that are "shot" into the cotton plant using a gene gun. The Bt toxin gene is isolated and inserted into a Ti plasmid from Agrobacterium tumefaciens. The engineered Ti plasmid is taken up by a bacterium that infects the cotton plant. A virus is engineered to contain the Bt toxin gene. This virus is then used to infect the plant and pass on the gene. The Bt toxin gene is added to water that is sprayed on the cotton plants. The gene is taken up through the roots of the plant.
The Bt toxin gene is isolated and inserted into a Ti plasmid from Agrobacterium tumefaciens. The engineered Ti plasmid is taken up by a bacterium that infects the cotton plant.
How do the strands separate during PCR? The DNA polymerase breaks the hydrogen bonds between the two strands. The primers separate the strands during the annealing step. The high heat of the denaturation step breaks the hydrogen bonds between the two strands. The cycling of the temperatures breaks the hydrogen bonds between the two strands.
The high heat of the denaturation step breaks the hydrogen bonds between the two strands
What is a thermocycler? The machine that controls the heat of the reaction, cycling between the different temperatures of the different steps during PCR The process of cycling through the different temperatures of a PCR reaction 30 times The special DNA polymerase, used in a PCR reaction, that can tolerate the high temperatures The name for the DNA primers used in a PCR reaction
The machine that controls the heat of the reaction, cycling between the different temperatures of the different steps during PCR
Which statement best describes restriction enzymes? They are necessary for the polymerase chain reaction (PCR) to occur. They can cut only circular plasmid DNA. They randomly cut DNA molecules to generate numerous fragments. They are important for cloning applications because they can be used to cut DNA at specific nucleotide sequences.
They are important for cloning applications because they can be used to cut DNA at specific nucleotide sequences.
How do restriction enzymes cut DNA sequences? They cut DNA at sites, called recognition sites, that have specific nucleotide sequences. They have the ability to cut DNA randomly. They cut DNA at sequences that have lots of adenine bases.
They cut DNA at sites, called recognition sites, that have specific nucleotide sequences.
What is the function of the primers in PCR? They provide a 3' end for the DNA polymerase. They provide energy for the DNA polymerization reactions. They polymerize free nucleotides to form the new DNA strands. They are the monomer building blocks from which the DNA strand is synthesized.
They provide a 3' end for the DNA polymerase.
In general, how might recombinant DNA technology be used to prevent a genetic disorder caused by a mutation in a single gene? To insert a desirable gene To insert a desirable gene, remove an undesirable gene, or replace a defective gene with a functioning gene To replace a defective gene with a working gene To remove an undesirable gene
To insert a desirable gene, remove an undesirable gene, or replace a defective gene with a functioning gene
What is the end goal of PCR? To allow cells to make DNA faster, thereby growing faster To increase the pool of different DNA sequences To quickly increase the number of copies of a specific DNA sequence
To quickly increase the number of copies of a specific DNA sequence
A shuttle vector is a plasmid that is used to move pieces of DNA among organisms, such as bacterial, fungal, and plant cells. True False
True
Bioinformatics is the use of computer technology to compare and analyze genome sequence. True False
True
If you used a broken thermocycler that could not heat above 75°C, which of the following problems could you expect? You would get more amplification than with a "normal" thermocycler. You would get some significant amplification, but less than if you used a "normal" thermocycler. You would not get any amplification of DNA. You would get the same amount of amplification as with a "normal" thermocycler.
You would not get any amplification of DNA.
Which of the following best describes a clone in the context of genetic modification procedures? an identical copy of the gene of interest a culture of genetically identical cells a cell that is genetically identical to its parent a vector, once it contains a copy of the gene of interest
a culture of genetically identical cells
A restriction fragment is a segment of mRNA. a segment of tRNA. a gene. a segment of DNA. cDNA
a segment of DNA.
A population of cells carrying a desired plasmid is called a library. vector. clone. PCR. Southern blot.
clone.
The use of an antibiotic-resistance gene on a plasmid used in genetic engineering makes replica plating possible. direct selection possible. the recombinant cell dangerous. the recombinant cell unable to survive. All of the answers are correct.
direct selection possible.
Foreign DNA can be inserted into cells using a variety of different methods. Which method involves the formation of microscopic pores in the cell's membrane? transformation protoplast fusion heat shock electroporation
electroporation
The reaction catalyzed by reverse transcriptase is DNA → DNA. tRNA → mRNA. mRNA → cDNA. mRNA → protein. DNA → mRNA.
mRNA → cDNA.
PCR stands for polymerase chain reaction. polymerization copying rapidly. polymerase copy reaction.
polymerase chain reaction.
Which of the following provides the specificity of the PCR reaction? separated DNA strands primers heating to 94°C Taq polymerase
primers
PCR can be used to identify an unknown bacterium because all cells have DNA. DNA can be electrophoresed. DNA polymerase will replicate DNA. the RNA primer is specific. all cells have RNA.
the RNA primer is specific
Which of the following processes is NOT involved in making cDNA? reverse transcription translation RNA processing to remove introns transcription
translation
Self-replicating DNA used to transmit a gene from one organism to another is a vector. Southern blot. clone. PCR. library.
vector.