Deck 9: Biotechnology and Recombinant Dna

Question 1

An ideal vector

A) may be a plasmid or bacteriophage.
B) has a restriction enzyme recognition site.
C) contains an origin of replication.
D) contains a selectable marker.
E) All of the choices are correct.

Answer 1

E

Question 2

The molecules used as molecular scissors in genetic engineering is/are

A) exonucleases.
B) proteases.
C) restriction enzymes.
D) RNA polymerase.

Answer 2

C

Question 3

Genetic engineering

A) allows the use of bacteria as production factories for a number of molecules.
B) relies on recombinant DNA technology.
C) is dependent on RNA enzymes.
D) relies completely on conjugation.
E) allows the use of bacteria as production factories for a number of molecules AND relies on recombinant DNA technology.

Answer 3

E

Question 4

Restriction enzymes have proved so useful in manipulating DNA because

A) they cut at defined sites.
B) the sticky ends make it very easy to allow recombination of any type of DNA.
C) they protect eukaryotes against virus attack.
D) they cut RNA molecules.
E) they cut at defined sites AND the sticky ends make it very easy to allow recombination of any type of DNA.

Question 5

A common vector used for cloning genes is/are

A) bacteria.
B) viruses.
C) nucleotides.
D) plasmids.

Question 6

The entire set of cloned fragments of the complete human genome is termed a

A) book of genes.
B) recombinant gene.
C) DNA library.
D) restructured genome.

Question 7

Host cells containing recombinant DNA can be selected on the basis of the properties of the

A) vector.
B) ribosomes.
C) enzymes.
D) virus.

Question 8

Digestion of DNA by restriction enzymes

A) produces sticky ends.
B) produces blunt ends.
C) cuts both strands of the DNA molecule.
D) generates restriction fragments.
E) All of the choices are correct.

Question 9

The molecule(s) that act as molecular glue to bind DNA fragments together is/are

A) DNAse.
B) DNA ligase.
C) ligandase.
D) polymerase.
E) DNAse AND ligandase.

Question 10

The energy to separate fragments during agarose gel electrophoresis is supplied by

A) gravity.
B) active transport.
C) agarosis.
D) electricity.

Question 11

The gene for human insulin has been successfully cloned in

A) S. aureus.
B) yeast.
C)E. coli.
D) rhinovirus.

Question 12

Agarose gel electrophoresis separates nucleic acid fragments according to

A) density.
B) shape.
C) size.
D) sequence.

Question 13

Selecting for transformants involves

A) identifying organisms that have taken up recombinant DNA.
B) searching for RNA.
C) production of proteins.
D) production of DNA.

Question 14

DNA molecules that contain pieces of DNA from two different sources are defined as

A) biotechnology.
B) gene cloning.
C) recombinant DNA.
D) genetic engineering.

Question 15

Mitochondrial DNA (mtDNA) in humans

A) is always donated to the offspring from both parents
B) can be used to identify related people
C) can be isolated only from intact embryos
D) can be used to establish paternity

Question 16

Laboratory strains ofE. coli are desirable hosts because

A) it is easy to grow.
B) its genetics is well known.
C) it is especially able to express foreign genes.
D) it has known phenotypic characteristics.
E) All of the choices are correct.

Question 17

The agarose used in electrophoresis

A) interacts electrically with the DNA.
B) chemically binds to the DNA.
C) acts as a sieve.
D) selectively sorts recombinant DNA from host DNA.

Question 18

Short tandem repeats (STRs)

A) are useful in identifying specific individuals
B) are important sites in vectors where foreign DNA can be integrated
C) are errors that can arise during DNA sequencing
D) are DNA fragments generated during PCR

Question 19

A dye often used for its ease and sensitivity to visualize nucleic acid after agarose gel electrophoresis is

A) nigrosin.
B) malachite green.
C) gold oxide.
D) ethidium bromide.

Question 20

Genetic engineering of plants has so far produced

A) pest resistant plants.
B) plants that are herbicide resistant.
C) plants with increased nutritional value.
D) All of the choices are correct.

Question 21

Genetically modified food has raised some concerns because

A) it contains radioactive particles.
B) it may contain some unanticipated allergens.
C) it may have some unintended environmental effects.
D) the modified DNA may transfer to other organisms.
E) it may contain some unanticipated allergens, it may have some unintended environmental effects AND the modified DNA may transfer to other organisms.

Question 22

The Ti plasmid is naturally found in

A) E. coli.
B) Pseudomonas.
C) Agrobacterium.
D) Staphylococcus.
E) E. coli AND Staphylococcus.

Question 23

The Ti plasmid is used as a vector to transfer DNA into

A) viruses.
B) bacteria.
C) plant cells.
D) animal cells.

Question 24

The polymerase chain reaction is used to

A) amplify certain sections of DNA.
B) amplify mRNA.
C) produce proteins.
D) produce long polymers of carbohydrates to be used in electrophoresis.

Question 25

Taq polymerase is

A) a reverse transcriptase.
B) an RNA polymerase.
C) from E. coli.
D) a heat stable DNA polymerase from Thermus aquaticus.
E) an RNA polymerase AND from E. coli.

Question 26

The current cost of sequencing a human genome is about

A) $ 10,000
B) $ 250,000
C) $ 1,000,000
D) $ 4,000,000

Question 27

Goal(s) of gene cloning may be to produce

A) a protein.
B) many copies of the gene to be used as a probe.
C) many copies of the gene for sequencing.
D) more copies of the host cell.
E) a protein, many copies of the gene to be used as a probe AND many copies of the gene for sequencing.

Question 28

In order to get around the lack of ability of prokaryotes to remove introns from precursor RNA, it may be necessary to

A) use the DNA directly.
B) use the DNA after it has been processed.
C) use different promoters.
D) turn mRNA into cDNA.
E) use the DNA directly AND use the DNA after it has been processed.

Question 29

Which of the following genera has proved useful for manipulating plant cells?

A) Escherichia
B) Bacillus
C) Pseudomonas
D) Agrobacterium

Question 30

Knowing the sequence of a genome is useful in

A) identifying genetic alterations associated with disease.
B) studying evolutionary relationships.
C) determining protein sequences.
D) All of the choices are correct.

Question 31

Starting with a single piece of dsDNA, after 3 PCR cycles there are

A) 2 additional pieces of dsDNA.
B) 4 additional pieces of dsDNA.
C) 8 additional pieces of dsDNA.
D) 16 additional pieces of dsDNA.

Question 32

Double-stranded DNA will separate into two strands when exposed to

A) high temperature.
B) high pH.
C) low temperature.
D) low salt.
E) high temperature AND high pH.

Question 33

PCR produces

A) DNA fragments of all possible sizes.
B) DNA fragments that are one nucleotide larger than the next fragment.
C) DNA fragments of a particular size.
D) DNA fragments of increasing size.
E) DNA fragments that are one nucleotide larger than the next fragment AND DNA fragments of increasing size.

Question 34

When a vector that employs the lacZ gene as a second marker is used in a cloning experiment, bacteria that harbor the recombinant DNA will give rise to

A) red colonies.
B) white colonies.
C) blue colonies.
D) All of the choices are correct.

Question 35

Dideoxynucleotides

A) are useful in nucleic acid sequencing.
B) have two additional hydroxyl groups at the 2' and 3' carbons.
C) act as chain initiators.
D) act as chain terminators.
E) are useful in nucleic acid sequencing AND act as chain terminators.

Question 36

DNA probes

A) may be obtained from denatured tagged dsDNA.
B) may be obtained from similar genes from another organism.
C) may be synthesized usually using information based on the protein sequence.
D) are usually tagged dsRNA.
E) may be obtained from denatured tagged dsDNA, may be obtained from similar genes from another organism AND may be synthesized usually using information based on the protein sequence.

Question 37

The polymerase chain reaction is used to duplicate small sections of

A) DNA.
B) RNA.
C) proteins.
D) lipids.

Question 38

The size of the amplified DNA fragment generated during PCR is determined by

A) how many cycles are performed.
B) the size of the template DNA.
C) the location to which the primers anneal.
D) how much Taq is used.

Question 39

A danger in using E. coli in cloning is that

A)E. coli could cause disease.
B) the human cells may reject the insertion.
C) the exons may invert the introns.
D) the outer membrane is poisonous to humans.

Question 40

PCR is particularly useful in

A) detecting viable yet non-culturable organisms.
B) assessing impure (multiple types of bacteria present) samples.
C) dealing with very small numbers of bacteria.
D) relatively quickly producing results.
E) All of the choices are correct.

Question 41

FISH uses labeled probes to detect specific whole cells.

Question 42

Fluorescence in situ hybridization (FISH)

A) uses virus hosts.
B) uses a labeled probe.
C) is useful in microbial ecology.
D) allows identification of particular bacterial groups in mixed samples.
E) uses a labeled probe, is useful in microbial ecology AND allows identification of particular bacterial groups in mixed samples.

Question 43

Polymerase chain reaction (PCR) can be used to perform DNA sequencing reactions. In this case, are 2 primers (a forward and a reverse) necessary?

A) Yes-you can't perform PCR without 2 specific primers to amplify the region in question in the DNA.
B) No-dideoxynucleotide sequencing depends on different length fragments being formed and then separated based on size. This can take place with only a specific forward OR a specific reverse primer.
C) No-you actually need a primer pair for each round of DNA amplification...so you'll need many, many primer pairs.
D) Yes-and it will be important to make sure that the primer pairs are made with dideoxynucleotides that are labeled with fluorescent dyes. Otherwise, you won't be able to detect the fragments that are made in the PCR process.

Question 44

Possessing the entire sequence of a particular human genome may not be as useful as we think. Why not?

A) Every human genome is different enough that knowing ONE human's DNA sequence can't tell us almost anything about ALL humans.
B) It's not the DNA sequence that matters-we need to know the mRNA sequence of the human genome.
C) Due to the presence of introns/exons, and splicing of RNA after transcription, the DNA sequence doesn't necessarily tell us the exact number/type of proteins that will eventually be made from it.
D) The amount of 'junk DNA' present in the human genome masks any useful genetic information that we'd like to obtain.

Question 45

In a FISH experiment, what would happen if unbound probe was not washed off?

A) Nothing-it's not necessary to wash off the unbound probe.
B) You would get false positive results in different areas where the probe hadn't actually bound, but it was still sitting there and lighting up.
C) Your FISH would be floating at the top of the tank due to the toxicity of the probe building up within them.
D) Nothing-the target nucleotide sequences are labeled, not the probe. Therefore, excess unbound probe wouldn't matter for the experiment.

Question 46

Most eukaryotic genes are cloned directly into the vector for expression in prokaryotes.

Question 47

PCR is useful for amplifying a particular section of DNA.

Question 48

A graduate student wants to clone a particular gene into a plasmid. The sequence includes AluI and BamHI sites on both sides of the desired fragment. AluI cuts symmetrically directly between the G and C nucleotides in a palindromic 5' AGCT 3' sequence. BamHI cuts asymmetrically directly between the G and G nucleotides in a palindromic 5' GGATCC 3' sequence. Which of the two restriction endonucleases should the graduate student choose, and why?

A) BamHI to cut both sides-since it cuts asymmetrically, it'll leave the sticky, cohesive single-strand DNA ends that will make it easier to ligate into a BamHI-cut plasmid DNA sequence.
B) AluI to cut both sides-it's always easier to ligate together blunt ends of DNA. She should also use AluI on the plasmid she wants to put the fragment into.
C) BamHI on the fragment, and AluI on the plasmid-this will give her the matching sequences to anneal/ligate together on the fragment/plasmid combination.
D) BamHI on one side of the fragment, and AluI on the other side-this would keep the fragment from sticking right back to where it was cut out from in the original DNA.

Question 49

A DNA microarray contains oligonucleotides that contain a label.

Question 50

Agarose gel electrophoresis may be considered as a partial purification technique.

Question 51

DNA microarray technology

A) may use many DNA fragments that function like probes.
B) attaches nucleotides to a solid support such as a glass slide.
C) relies on arrays that contain a detectable tag.
D) uses nucleic acid hybridization.
E) may use many DNA fragments that function like probes, attaches nucleotides to a solid support such as a glass slide AND uses nucleic acid hybridization.

Question 52

DNA probes are used to find regions of complementary DNA.

Question 53

A very common vector is a plasmid.

Question 54

When using lacZ containing vectors, colonies containing intact vector turn blue.

Question 55

Vectors must have at least one restriction enzyme recognition site.

Question 56

PCR typically results in the generation of fragments of all sizes.

Question 57

A common way to identify the

A) vector.
B) probe.
C) host.
D) plasmid.
E) coli that carries the desired recombinant DNA is by using a