Deck 5: Molecular Tools for Studying Genes and Gene Activity

Question 1

A DNA fragment was treated with EcoRI restriction enzyme.The restriction pattern is shown below.How many fragments should be visible on a Southern blot if radioactively labeled probe "1" was used?

A)0
B)1
C)2
D)3
E)4

Answer 1

D

Question 2

A technique is needed to rapidly separate positively charged histone proteins from a crude cell extract.Which of the following should be chosen?

A)SDS-PAGE
B)phosphocellulose cation-exchange chromatography
C)pulse-field gel electophoresis
D)gel filtration chromatography
E)DEAE-Sephadex chromatography

Answer 2

B

Question 3

During SDS PAGE,which of the following does not directly affect the migration of the polypeptides through the gel?

A)the size of the polypeptide
B)the strength of the electric field
C)the molecular mass of the protein
D)the native charge on the polypeptides
E)the SDS

Answer 3

D

Question 4

It is suspected that a novel histone protein only interacts with the promoter region of $\beta$ -globin genes.Which of the following techniques should be used to confirm this suspicion?

A)EMSA
B)DNase footprinting
C)filter binding
D)gel mobility shift assay
E)all of the choices are correct.

Question 5

In molecular biology all of the following methods can detect small traces of radioactivity except

A)liquid scintillation counting.
B)autoradiography.
C)x-ray film.
D)phosphorimaging.
E)spectrophotometry.

Question 6

Which of the following isotopes would be the most appropriate for the end-labeling of a DNA strand with a radioactive phosphate?

A) $\alpha$ -³²P
B)³⁵S
C) $\beta$ -³²P
D) $\gamma$ -³²P
E)¹⁴C

Question 7

Which of the following is a substrate for $\beta$ -galactosidase?

A)lacZ
B)chloramphenicol
C)X-gal
D)acetyl-CoA
E)both lacZ and acetyl-CoA

Question 8

Which of the following is not used in a Sanger chain termination reaction?

A)ddATP
B)ddUTP
C)ddCTP
D)ddGTP
E)ddTTP

Question 9

Site-directed mutagenesis is used for which of the following purposes?

A)to insert fragments of more than 100 pairs into a specific DNA site
B)to induced site-specific recombination
C)to make changes to specific bases in DNA
D)to remove large segments of a DNA sequence
E)Both to induced site-specific recombination and to make changes to specific bases in DNA are correct.

Question 10

Which of the following is used to study the interaction of proteins with DNA?

A)S1 nuclease protection
B)DNase-1 footprinting
C)DNA fingerprinting
D)southern analysis
E)northern blotting

Question 11

Which of the following techniques is not used to quantify the level of gene expression?

A)southern blotting
B)northern blotting
C)S1 mapping
D)RNase protection
E)nuclear run-off

Question 12

The SELEX method is used for which of the following?

A)discover short RNA sequence that interact with other molecules
B)assay transcriptional levels abundant aptamers
C)evaluate transcribed regions of DNA
D)discover new mutations in rRNA sequences
E)none of the choices are correct.

Question 13

Rapid purification of proteins based on size can best be done using

A)gel filtration.
B)ion-exchange chromatography.
C)native gel electrophoresis.
D)2-D gel electrophoresis.
E)cation-exchange chromatography.

Question 14

A 3000 bp circular DNA was treated with both HindIII and EcoRI restriction enzymes.EcoRI cuts at position 100.HindIII cuts at positions 500 and 2000.Which of the following represents the fragment that would be observed if the restricted DNA were analzyed using agarose gel electrophoresis?

A)400,100,1000,1500
B)400,500,1500
C)400,100,1600
D)500,100,500,900
E)500,1000,600

Question 15

Which of the following can be used to establish relatedness between individuals?

A)DNA fingerprinting
B)DNA typing
C)RFLP analysis
D)DNAse footprinting
E)DNA fingerprinting,DNA typing,and RFLP analysis are correct.

Question 16

A circular 3000 bp UC18 plasmid DNA sample was treated with BamHI restriction enzyme.The plasmid has restriction sites at position 100 and position 2000.Which of the following choices represents the size fragments that would be observed on an agarose gel?

A)2900,100
B)1900,100,1000
C)1900,1100
D)2900,50,50
E)1900,50,50,1000

Question 17

A new insulin gene was isolated and a study was planned to look at the function of the promoter region.Which of the following would be the best choice for this study?

A)southern analysis
B)immunoblotting
C)reporter gene assay
D)PCR
E)immunoprecipitation

Question 18

A major function of reporter gene assays is to

A)measure mutation rates of a gene.
B)measure transcriptional levels.
C)measure replication.
D)monitor luciferase activity.
E)monitor CAT activity.

Question 19

A set of six probes was used to compare a DNA sample taken from a crime scene to the DNA of an arrested suspect.Each probe can detect one in every one hundred persons.Results showed that all six probes detected identical patterns in both DNA specimens.What is the chance for a match using all six probes?

A)1 in 106
B)1 in 1010
C)1 in 1011
D)1 in 1012
E)1 in 108

Question 20

Which of the following is not true about run-on transcription assay?

A)Isolated nuclei are used in the assay.
B)Cytoplasmic RNA is included in the assay.
C)The reaction is done in the presence of labeled nucleotide.
D)The assay can reveal the transcription rates of genes
E)Genes being transcribed can be identified.

Question 21

__________ is a means of detecting radioactive compounds with photographic emulsion.

Question 22

_____________ ________________ can be used to produce disrupted genes in several organisms.

Question 23

The best method for separating large DNA fragments greater that 1Mb is by electrophoresis in 1% agarose gels.

Question 24

Primer extension can be used to locate the exons in a transcript.

Question 25

The G-less cassette assay is conducted using a promoter fused to a short DNA sequence and can be used to measure the transcription activity in a cell.

Question 26

A ________________ map is used to indicate the positions on genes on a chromosome.

Question 27

____________ is a method used to detect DNA-protein interactions.

Question 28

Fluorescence in situ hybridization can be used to locate genes on individual chromosomes.

Question 29

During the first phase of two-dimensional gel electrophoresis,each polypeptide migrated based on its molecular mass.

Question 30

A study was conducted to identify a liver cell gene (zed)that has a length of 3000 bp.A southern blot was prepared using DNA from the liver cell and a probe made to region 1600-2000 of zed.Analysis of the blot revealed that there are two spots present,one at 3000 and another at 2000.A plausible explanation for this observation is:

A)there is an identical copy of this gene on another chromosome.
B)the gene was cut in two equal portions by a restriction enzyme.
C)there is a another gene with sequence similar to gene zed.
D)both there is an identical copy of this gene on another chromosome and there is a another gene with sequence similar to gene zed are correct.
E)no explanation can be given using the available data.