Deck 4: Molecular Cloning Methods

Question 1

A new enzyme was isolated and found to have a recognition sequence of 5 base pairs.How often will it cut in a genome?

A)64
B)4096
C)8192
D)1024
E)3124

Answer 1

D

Question 2

One approach to prevent religation of the ends of a restricted plasmid DNA is to

A)store the plasmid in DNase.
B)store the plasmid in RNAase.
C)treat the plasmid with alkaline phosphatase to remove phosphates from the 'sticky ends'
D)treat the plasmid with a protease to remove all proteins.
E)treat the plasmid with BamHI to create gaps.

Answer 2

C

Question 3

The complementary sequence of one of the following is a palindrome.Which one?

A)GAATTC
B)CTGACT
C)ATCCTC
D)GGCCAA
E)CCTTTC

Answer 3

A

Question 4

Which of the following is ideal for screening a protein expression library?

A)labeled antibodies
B)3'RACE
C)5' RACE
D)RT-PCR
E)Real-Time PCR

Question 5

A molecular biologist is able to select recombinant colonies from a bacterial culture plate based on the color of the colonies.Which of the following is a correct statement?

A)Colonies that contain recombinant plasmids are red.
B)Colonies that contain recombinant plasmids are blue due to the disruption of the lacZ gene the insert.
C)Colonies that contain recombinants are clear/white due to the disruption of the lacZ gene by the insert.
D)Colonies are blue due to the disruption of the ampicillin gene.
E)All of the choices are correct.

Question 6

The correct 10-base forward PCR primer starting at position 5 on the following sequence would be 5'-ATGCCGATGTAGGGCGGGATGGAGAGATAGAGAGAGTCACAAT-3'

A)5-GGGATGGCAT
B)5'-ATGCCGATGT
C)5'-CGATGTAGGG
D)5'-GAGTCACAAT
E)5'-GCTACATCCC

Question 7

Which of the following vectors is useful in producing single-stranded DNA?

A)puc18
B) $\lambda$ phage
C)M13
D)BAC
E)YAC

Question 8

Which of the following vectors is the best choice for the expression of eukaryotic proteins?

A)M13
B)baculovirus
C)phagemid
D)pUC18
E)pUC19

Question 9

A recombinant plasmid was constructed with several restriction enzyme sites and an ampicillin resistance marker.This recombinant was used to transform a host bacteria that also has the ampicillin resistant gene.Which of the following statements is true regarding this experiment?

A)All transformed bacteria will grow on a plate containing ampicillin.
B)All untransformed bacteria will grow on a plate containing ampicillin.
C)It will be difficult to screen for a colony containing a plasmid.
D)A bacterial host that is ampicillin-sensitive should be used for the screening.
E)All of the choices are true.

Question 10

Which of the following is true regarding alpha complementation?

A)The plasmid encodes the amino terminal of $\beta$ -galactosidase while the host bacterium encodes the carboxyl portion .
B)The plasmid encodes both amino and carboxyl terminals of the lacZ region.
C)The complete $\beta$ -galactosidase enzyme is made by the host.
D)When the alpha and beta regions fuse they form an inactive peptide.

Question 11

Which of the following enzymes cannot catalyze the formation of a phosphodiester bond?

A)endonuclease
B)RNA polymerase
C)DNA polymerase
D)ligase
E)none of the choices are correct.

Question 12

A bacterial sample was contaminated with an unknown preparation of vector DNA.In order to identify the vector,the bacteria was streaked on a plate and incubated overnight.Examination of the plate revealed at least 120 clear plaques.Which of the following is a plausible conclusion?

A)The vector could be a plasmid.
B)The vector could be a phage.
C)The vector is a Ti.
D)The vector is puc18.
E)The vector is a cosmid.

Question 13

The "Flavr Savr" tomato is generated by

A)the introduction of plasmids into tomatoes.
B)introducing the antisense copy of the gene that contributes to ripening.
C)the inhibition of transcription of most genes in the tomato.
D)the introduction of the sense copy of the gene that contributes to ripening.
E)the introduction of plasmids into tomatoes and the introduction of the sense copy of the gene that contributes to ripening are correct

Question 14

Restriction enzymes were discovered by

A)Boyer and Cohen.
B)Linn and Arber.
C)Watson and Crick.
D)Gurdon and Linn.
E)Cohen and Gurdon.

Question 15

A disadvantage of using a prokaryotic expression system for eukaryotic proteins is that the proteins are

A)highly phosphorylated after translation.
B)improperly folded.
C)highly soluble.
D)heavily glycosylated.
E)over expressed.

Question 16

Which of the following enzymes will produce blunt-ended cuts in DNA?

A)EcoRI
B)HindIII
C)SmaI
D)BamHI
E)PstI

Question 17

What is the RACE technique?

A)screening a genomic library
B)extending incomplete cDNA sequences
C)generating polynucleotide probes
D)rapid amplification of genomic DNA
E)screening a genomic library and generating polynucleotide probes

Question 18

In constructing a cDNA library,which of the following would you use to generate rare restriction sites on the cDNA strands?

A)restriction enzymes
B)PCR with multiple cycles
C)BamHI restriction followed by ligation
D)ligate cDNA to specific linkers
E)5'RACE

Question 19

How many enzymes should be used to cut the plasmid DNA and the insert DNA if there is a desire to ligate the insert within the vector in a specific orientation?

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

Question 20

Select the component that is most critical to the function of a plasmid.

A)tetracycline resistance
B)ampicillin resistance
C)EcoRI site
D)origin of replication
E)ligase

Question 21

The use of high voltage to drive DNA into cells is called _____________.

Question 22

A group of identical cells is called a __________.

Question 23

Bacteria use the restriction-modification system to synthesize new DNA molecules.

Question 24

In the construction of an expression vector,which of the following would you include in order to stimulate a high level of RNA synthesis?

A)P3
B)T7 phage promoter
C)Ampr gene
D)His region
E)GFP

Question 25

A fusion protein can easily be isolated by ____________________ chromatography.

Question 26

A fragment restricted with EcoRI enzyme can be used for ligation into a plasmid that was restricted with BamHI because both the insert and the plasmid contain sticky ends.

Question 27

An enzyme that recognizes different sites in an identical sequence is called a ____________.

Question 28

HindIII is so named because it was isolated from Haemophilus influenzae bacterium.

Question 29

In a replacement vector,a portion of the DNA is removed to accommodate the fragment to be inserted.

Question 30

Polynucleotide probes can be used to screen a genomic library for specific genomic sequences.