mastering microbiology chapter 9

any genetically modified bacteria are programmed with a self-destructive gene that will eventually destroy the organism. T/F

true

dna fingerprints are actually

dna fragments

Special considerations must be taken when using bacteria to produce a eukaryotic protein. What is the cause for this additional difficulty? Transcription is in prokaryotes is very different from transcription in eukaryotes. Eukaryotic genes contain introns, which prokaryotic cells cannot remove. Prokaryotic DNA contains different nucleotides. Translation in prokaryotes is very different from translation in eukaryotes

Eukaryotic genes contain introns, which prokaryotic cells cannot remove.

cDNA is made from

an mRNA template

southern blotting is used to

identify particular sequences of dna

A disadvantage of using E. coli to produce recombinant proteins for human pharmaceuticals is the possibility of endotoxin contamination. T/F

true

Which of the following is an example of a cloning vector? plasmid tick human growth hormone mosquito ribosomal RNA

plasmid

Recombinant DNA can be introduced into a host cell by any of the following methods EXCEPT __________. protoplast fusion transformation polymerase chain reaction microinjection electroporation

polymerase chain reaction

Sequencing a genome provides __________. restriction fragments a gene sequence identity of proteins expressed by the cell the order of nucleotides in a genome

the order of nucleotides in a genome

If a recombinant plasmid is put in solution with E. coli, the bacteria may pick up the plasmid by __________.

transformation

The cells are phe- and the media lack phenylalanine. Why are the phe- cells growing on plate C?

transformation

Viral DNA is an important cloning vector because it can typically be combined with relatively large pieces of DNA. T/F

true

An ampicillin-sensitive culture of E. coli is transformed with a plasmid that contains the gene of interest plus an ampicillin-resistant gene. If it is then plated on an ampicillin-containing growth medium, __________. no bacteria will grow only the lactose-positive bacteria will grow only the ampicillin-sensitive bacteria will grow only the bacteria with the plasmid will grow all gram-negative bacteria will grow

only the bacteria with the plasmid will grow

Which of the following might specifically be used as part of a reverse-genetics approach to studying a gene? PCR Ti plasmid reverse transcriptase RNA interference Southern blotting

RNA interface

which of these statements is true for restriction enzymes

Restriction enzymes are useful in genetic engineering when they make staggered cuts in DNA.

For which of the following applications can PCR be used? sequencing DNA making copies of a gene to be put into another organism identifying traits that may lead to a genetic disorder all of the above none of the above

all of the above

Which of the following is a safety issue related to the use of recombinant DNA? reduction in populations of "desirable" insects due to the use of Bt insecticide allergic reactions to components in genetically modified foods spread of bioengineered traits, such as herbicide resistance, into related weed species all of these End of Question 20

all of these

If you put the gene for Bt toxin from Bacillus thuringiensis into a tomato plant, the resulting plants will __________. die be toxic to insects that eat them have a Bacillus infection be toxic to humans who eat the tomatoes

be toxic to insects that eat them

What is/are the role(s) of dNTPs in a PCR? They are the monomers for the DNA strand to be synthesized. They provide energy for the DNA polymerization to occur. Both of the above answers apply. Neither of the above answers applies.

both of the above answers apply

Which of the following is not a constituent of PCR? DNA primers dUTP target DNA dATP DNA polymerase End of Question 2

dUTP

In nature, the function of restriction enzymes is to __________.

destroy bacteriophage dna

A plasmid that has been cleaved with EcoRI can recombine with another plasmid that has been __________. digested with EcoRI digested with HindIII amplified by PCR cleaved with BamHI

digested with EcoRI

DNA can be introduced into plant cells only if the cell wall is first removed. T/F

false

If a foreign gene inserted into a plasmid inactivates the beta-galactosidase gene, a bacterium containing that plasmid would form blue colonies on the X-gal medium. T/F

false

For Agrobacterium tumefaciens to be used to introduce foreign DNA into a plant cell, that DNA must first be __________. inserted into the Ti plasmid of A. tumefaciens outside the T-DNA region inserted in an A. tumefaciens plasmid other than the Ti plasmid inserted into the main chromosome of A. tumefaciens isolated from the crown gall using the appropriate restriction enzyme inserted into the T-DNA region of the Ti plasmid of A. tumefaciens

inserted into the T-DNA region of the plasmid of A tumefaciens

why is a tempertautre of 94 required for pcr

it allows the strands of target dna to seperate

In genetic engineering, antibiotic resistance genes are often cloned into a vector to __________.

make direct selection of a clone possible

A good cloning vector __________. should be readily degraded in the host should not be able to be cut by more than one restriction enzyme should not be capable of replication should have a gene or genes that allows for selection of transformed host cells should have a high concentration of guanine

should have a gene or genes that allows for selection of transformed host cells

lasmids that can exist in disparate species such as a bacterium and a plant cell are called __________ vectors, and they can be used to transfer cloned DNA from one type of organism to another.

shuttle

what is the ultimage goal of recombinant dna technology

to improve the organisms

If a foreign gene inserted into a plasmid inactivates the β-galactosidase gene, a bacterium containing that plasmid would form blue colonies on X-gal medium. T/F

true

Place the following steps of PCR in order: Annealing of primers Separation of strands Synthesis of new DNA

2,1,3

Put the following events of PCR in order: Repeat 30+ times. Denature at 94oC. Extend at 72oC. Prime at 60oC.

2,4,1,3

Which of the following statements correctly differentiates biotechnology from rDNA technology? Biotechnology includes genetic modification of eukaryotic cells and prokaryotic cells, whereas rDNA technology exclusively involves the genetic modification of bacteria. Biotechnology is concerned only with the production of recombinant proteins, whereas rDNA technology is concerned exclusively with DNA. Biotechnology includes techniques for gene amplification, whereas rDNA technology includes techniques for altering the nucleotide sequence of an organism's DNA. Biotechnology involves any use of microorganisms or cells to make products, regardless of the means used. Recombinant DNA technology involves methods for handling and modifying DNA and inserting it into different types of cells.

Biotechnology involves any use of microorganisms or cells to make products, regardless of the means used. Recombinant DNA technology involves methods for handling and modifying DNA and inserting it into different types of cells.

The following sequential steps are used to make a recombinant cell. Which of these steps occurs LAST? Isolate gene of interest. Grow cells containing vector with gene. Insert gene into a vector. Vector is taken up by cell.

Grow cells containing vector with gene.

Which of the following statements correctly differentiates a genomic library from a cDNA library? Genomic libraries are prepared from eukaryotes, and cDNA libraries are prepared from prokaryotes. Genomic libraries contain only those genes that a cell is currently expressing, whereas cDNA libraries contain all of the cell's genes, whether expressed or not. A genomic library contains only noncoding DNA sequences, whereas a cDNA library contains only coding sequences. cDNA libraries can be used for sequencing, but they cannot be transcribed and translated. Genomic libraries can be used for sequencing and for production of the desired protein product. A genomic library contains fragments of the entire DNA in an organism's genome. A cDNA library contains the coding sequences of eukaryotic genes (minus the introns).

a genomiv library contains fragments of the entire DNA in an organisms genome. A cDNA library contains the coding sequences of eukaryotic genes minus the introns

Which of the following is NOT a step in Southern blotting? addition of a radioactive probe made from the gene of interest transfer of DNA fragments to filters separation of DNA fragments by gel electrophoresis digestion of sample DNA with restriction enzyme addition of heat-stable DNA polymerase

addition of heat stable polymerase

Which of the following can result once the recombinant DNA molecule has been made? It is inserted into a host cell. It is copied many times inside a host cell. It can be transcribed and then translated into a desired protein. All of the above actions can result. None of the above actions can result. End of Question 4

all of the above can result

Which of the following can be used as vectors to genetically modify cells? plasmids viruses shuttle vectors all of these End of Question 4

all of these

In genetic engineering, antibiotic-resistance genes are usually cloned into vectors to __________. allow selection for bacteria containing the vector select for cells having undergone spontaneous mutation kill the recombinant organisms select for cells that cannot grow

allow selection for bacteria containing the vector

Assume you insert a specific gene into a plasmid and use blue-white screening. You plate the transformed E. coli cells on an ampicillin X-gal medium. Cells that produce blue colonies are __________. ampicillin resistant but do not contain the new gene ampicillin resistant and contain the gene of interest ampicillin sensitive and can hydrolyze X-gal ampicillin sensitive and cannot hydrolyze X-gal

ampicillin resistant but do not contain the new gene

When two DNA pieces cut with the same restriction enzyme are combined, sticky ends will __________. associate by covalent bonds associate because of DNA ligase associate only if they are double-stranded not associate associate by complementary base pairing and hydrogen bonds

associate by complementary base pairing and hydrogen bonds

If DNA ligase were NOT used in the creation of a recombinant plasmid, __________. the bacterium to receive the recombinant plasmid would not be competent and thus would be unable to take up the plasmid base-pairing would occur but the sugar phosphate backbone would not be connected links between adenine and thymine would not occur hydrogen bonds between complementary bases could not form links between guanine and cytosine would not occur

base pairing would occur but the sugar phosphate backbone would not be connected

The use of microorganisms, cells, or cell components to make products such as hormones, antibiotics, food, or vaccines is known as __________.

biotechnology

For the introduction of a genetically modified plasmid into E. coli, __________. protoplast fusion must be used no treatment is needed, because the cells are naturally competent microinjection must be used a gene gun must be used calcium chloride and heat shock can be used

calcium chloride and heat shock can be used

To express a human gene in a bacterium, cDNA must be made because bacteria __________. have reverse transcriptase usually destroy human DNA splice RNA cannot remove introns

cannot remove introns

Recombinant DNA technology is used for all of the following EXCEPT ________. insertion of genes from humans or plants into bacteria or viruses human-insulin production by bacterial cells amplification of DNA for microbe identification hepatitis-B-vaccine production using yeast cells culturing unknown organisms

culturing organisms

Recombinant DNA technology is used for all of the following EXCEPT __________. human-insulin production by bacterial cells insertion of genes from humans or plants into bacteria or viruses culturing unknown organisms amplification of DNA for microbe identification hepatitis-B-vaccine production using yeast cells

culturing unknown organisms

Real-time PCR differs from traditional PCR in that real-time PCR amplification is monitored by gel electrophoresis. T/F

false

Yeasts can only be genetically engineered to express foreign, prokaryotic genes. T/F

false

ll restriction enzymes produce short stretches of single-stranded DNA called "sticky ends." T/F

false

What is unique about the DNA polymerase in PCR? It synthesizes DNA from the 3' direction to the 5' direction. It does not require primers. It can separate strands of DNA. It can withstand the high temperatures needed for PCR.

it can withstand the high temperatures of pcr

Which of the following is NOT true of the polymerase chain reaction (PCR)? A heat-stable DNA polymerase is used in the reaction process. Short pieces of DNA called primers are added to the reaction mixtures. Billions of copies of a DNA sequence are made in a few hours. Large amounts of DNA must be isolated from the source organism. An automated thermocycler is used to heat and cool the reaction samples.

large amounts of DNA must be isolated from the source organism

In the blue-white screening procedure, bacteria that are transformed with recombinant plasmid and cultured in media containing ampicillin and X-gal will __________. produce white colonies grow more rapidly than cells without recombinant DNA not grow in this medium produce blue colonies produce the enzyme beta-galactosidase

produce white colonies

Which of the following is NOT an advantage of obtaining the protein product called human growth hormone by recombinant DNA technology rather than extraction from cadavers?

production of endotoxins

Restriction enzymes ________.

recognize palindromic double-stranded sequences of DNA and cut the DNA in a specific location

Which of the following cuts DNA at specific sequences? plasmids restriction enzyme DNA ligase

restriction enzymes

Which of these statements is true for restriction enzymes? A different restriction enzyme must be used to open the vector DNA than to excise the gene sequence to be cloned. Restriction enzymes are useful in genetic engineering when they make staggered cuts in DNA. A given restriction enzyme will always recognize the same DNA sequence, but it will cut differently depending on the species of origin of the DNA. Any restriction enzyme can cut any piece of DNA. Each restriction enzyme is able to make a staggered cut at its recognition site.

restriction enzymes are useful in genetic engineering when they make staggered cuts in dna

the shotgun sequencing technique is used to

sequence entire genomes

Which of the following statements about PCR is true? The number of DNA doubles after each cycle. After each round of PCR, you will have one new strand of target DNA. The phosphodiester bond between each nucleotide is broken during the denaturation step. After 30 rounds of PCR, the target DNA has been amplified several thousand times.

the number of dna doubles after each cycle

During the Southern blotting technique, what is the purpose of transferring the DNA fragments from the gel to a nitrocellulose filter? This step prepares the DNA fragments for PCR. This step selects and transfers only the genes of interest. This step separates the two complementary DNA strands. This step attaches the DNA fragments to a permanent substrate, which then can be probed. This step prepares the DNA for digestion by restriction enzymes.

this step attaches the DNA fragments to a permanent substrate which then can be probed

Why must the recipient plasmid be cut with the same restriction enzyme? to prevent the donor from receiving the same genetic information to allow for a site in the plasmid for the donor DNA to attach to remove the donor DNA from the plasmid all of the above none of the above

to allow for a site in the plasmid for the donor dna to attach

Which of the following is NOT a purpose of genetic modification? to modify the characteristics of an organism to create proteins used in vaccines (e.g., hepatitis B vaccine) to create multiple copies of a gene of interest to create hormones such as insulin or human growth hormone to remove antibiotic resistant plasmids from bacteria

to remove antibiotic resistant plasmids from bacteria

E. coli may pick up a recombinant plasmid from a solution by __________.

transformation

The basic steps to genetically modify a cell are listed below. Which step would come LAST? restriction digestion of gene restriction digestion of vector ligation transformation

transformation

In protoplast fusion, a chemical can induce fusion between the two wall-less cells. T/F

true

All of the following are benefits and improvements made possible by recombinant DNA technology EXCEPT __________. improved weed and pest control development of genetic screening procedures for early detection of genetic diseases use of baker's yeast to produce bread development of new, safer vaccines

use of bakers yeast to produce bread