Deck 14: The Techniques Of Molecular Genetics

Question 1

Which of the following can be determined using a cloned gene? 1.A gene's nucleotide sequence
2)A gene's function
3)A gene's amino acid sequence

A) 1
B) 2
C) 3
D) 1 and 2
E) All of these

Answer 1

E

Question 2

In a gene cloning procedure the GFP gene is inserted into a plasmid and the plasmid is then taken up through transformation into an E.coli cell where it replicates.In which portion of this gene cloning procedure is the recombinant DNA molecule constructed? 1.The GFP is inserted into the plasmid
2)The plasmid is taken up via transformation
3)The plasmid replicates in the E.coli cell

A) 1
B) 2
C) 3
D) 1 and 2
E) 2 and 3

Answer 2

A

Question 3

What method allows bacteria to protect endogenous restriction sites from being cleaved by restriction enzymes?

A) Methylation
B) Amylation
C) Glycosylation
D) Methylation and Amylation
E) None of these

Answer 3

A

Question 4

Which of the following techniques allow researchers to isolate and characterize DNA sequences?

A) Recombinant DNA techniques
B) Gene cloning
C) DNA amplification
D) Gene cloning and DNA amplification
E) All of these

Question 5

Small self replicating genetic elements used to clone genes are known as:

A) Cloner sections
B)Cloning vectors
C) Cloning sequences
D) Restriction enzymes
E) Silencers

Question 6

Which of the following is not commonly used as a cloning vector?

A) Plasmid
B) Cosmid
C) Phagemid
D) Bacteriphage
E) All of these are commonly used vectors

Question 7

What is the natural biological function of restriction endonucleases?

A) To clone genes in eukaryotic sequences
B) To protect viruses from bacterial invasion
C) To protect bacteria from viral invasion
D) To protect eukaryotes from bacterial invasion
E) To clone genes in prokaryotic sequences

Question 8

Which enzyme is used to join two complementary DNA fragments after a cut has been made?

A) restriction endocnucleases
B) RNA polymerase
C) DNA gyrase
D) DNA ligase
E) Helicase

Question 9

Which of the following enzymes is required for sequencing a gene?

A) RNA polymerases
B) DNA gyrases
C) Restriction endonucleases
D) Lactases
E) None of these

Question 10

A cluster of unique restriction sites in a cloning vector is often referred to as a/an:

A) Polylinker
B) Polycloning site
C) Unilinker
D) Polylinker and Polycloning site
E) All of these

Question 11

Most of today's bacteriophage cloning vectors are derived from which phage?

A) SV40
B) T4
C) Lambda
D) T2
E) pGLO

Question 12

Which of the following is not a feature of restriction enzymes?

A) They recognize palindromic sequences
B) They make staggered cuts
C) They cut at random sites
D) They are named after the species in which the enzyme is produced
E) All of these are true

Question 13

A DNA molecule containing DNA fragments from two or more different sources is known as a:

A) Recombinant DNA molecule
B) Mutated DNA molecule
C) Biologically normal DNA molecule
D) Wild type DNA molecule
E) Homeric DNA molecule

Question 14

In a certain procedure,short DNA strands that are complementary to DNA sequences on either side of the gene or DNA sequence of interest are synthesized and used to initiate its amplification in vitro by a special (heat-stable)DNA polymerase.The procedure is known as:

A) Telomerase Chain Reaction
B) Polymerase Chain Reaction
C) Gene cloning
D) DNA fingerprinting
E) Restriction Fragment Length Polymorphism

Question 15

In a gene cloning procedure the GFP gene is inserted into a plasmid and the plasmid is then taken up through transformation into an E.coli cell where it replicates.In which portion of this procedure is gene cloning actually taking place? 1.The GFP is inserted into the plasmid
2)The plasmid is taken up via transformation
3)The plasmid replicates in the E.coli cell

A) 1
B) 2
C) 3
D) 1 and 2
E) 2 and 3

Question 16

Which of the following was used to create many of today's plasmid cloning vectors?

A) pBR322
B) pGLO
C) pBAC
D) pGFP
E) pBLU

Question 17

Why is it possible to join a piece of DNA from a human that has been digested using EcoR1 and a piece of DNA from a bacterium that has been digested using EcoR1?

A) They have been cut with the same restriction enzyme therefore the staggered ends are the same and are complementary
B) Bacteria and humans exist in a symbiotic relationship and therefore share DNA and can be joined together
C) They can join together only in the presence of high heat and pressure, such as is found in an autoclave.
D) They can not join together because the DNA has come from two different species and even though they are digested with the same restriction enzyme the cuts are at different locations.
E) All of these

Question 18

Which of the following is true regarding restriction enzymes?
1)Methylation protects an organism's DNA from cutting by restriction enzymes
2)Restriction enzymes are exonucleases
3)Restriction enzymes can make staggered or blunt cuts

A) 1
B) 2
C) 3
D) 1 and 2
E) 1 and 3

Question 19

Which of the following types of restriction enzymes cleave DNA at only specific nucleotide sequences known as restriction sites,regardless of the source of the DNA?

A) Type I
B) Type II
C) Type III
D) Type IV
E) Type V

Question 20

Which of the following is an essential component in a cloning vector?

A) Origin of replication
B) Selectable marker gene
C) Unique restriction enzyme site
D) Origin of replication and Unique restriction enzyme site
E) All of these

Question 21

Which of the following statements about phagemid vectors is incorrect?

A) They contain components from both phage chromosomes and plasmids
B) They require a helper phage to replicate and package single stranded DNA particles in phage heads
C) An example of a phagemid vector is pUC118
D) Can allow researchers to perform directional cloning
E) All of these

Question 22

Why is Taq polymerase used more commonly in PCR than DNA polymerase I from E.coli?
1)Taq polymerase remains active during the high heat denaturation step unlike DNA polymerase I
2)Taq polymerase is less expensive than DNA polymerase I
3)Taq polymerase must be added after each deanturation step unlike DNA polymerase I

A) 1
B) 2
C) 3
D) 1 and 2
E) All of these

Question 23

Which portion of the lambda phage can be excised and used for the insertion of foreign DNA?

A) The external portions required for lytic growth
B) The central portion required for lysogenic growth
C) The external portions required for lysogenic growth
D) The central portion required for lytic growth
E) No part can be excised, but extra DNA can be added in

Question 24

Which of the following is the correct order of steps in PCR?

A) Extension of DNA, denaturation of DNA, annealing of primers
B) Denaturation of DNA, extension of DNA, annealing of primers
C) Denaturation of DNA, annealing of primers, extension of DNA
D) Annealing of primers, extension of DNA, denaturation of DNA
E) Annealing of primers, denaturation of DNA, extension of DNA

Question 25

The purpose of the primer sequence in PCR is to:

A) Provide a promoter sequence for DNA polymerase
B) Provide a free 3'-OH end required for covalent extension
C) Allow for efficient denaturation of the double stranded DNA
D) Keep the DNA denatured after the temperature is reduced
E) All of these

Question 26

Filamentous single-stranded DNA phages infect cells by absorbing to which of the following structures?

A) Cell membrane
B) F pili
C) Cell wall
D) Nucleus
E) Mitochondria

Question 27

cDNA libraries contain only:

A) The non coding regions of expressed genes
B) The coding regions of expressed genes
C) The non coding and coding regions of non-expressed genes
D) All of these
E) None of these

Question 28

Which type of vector can replicate in both E.coli and another species?

A) Plasmids
B) Lambda phage
C) Cosmids
D) Shuttle vectors
E) None of these

Question 29

A disadvantage of l cloning vectors is:

A) An inability to accommodate eukaryotic DNA
B) The absence of unique restriction sites
C) An inability to be packaged in vitro
D) A strict limit on the insert size (no larger than 10kb)
E) The instability of large foreign DNA inserts

Question 30

What does the enzyme reverse transcriptase do?

A) Degrades foreign DNA
B) Synthesizes RNA complementary to a DNA template
C) Synthesizes DNA complementary to an RNA template
D) Inactivates restriction endonucleases
E) Adds nucleotides to the end of DNA molecules

Question 31

Which of the following is found in a YAC?

A) Yeast origin of replication
B) Two yeast telomeres at the end of the minichromosome
C) Yeast centromere
D) Polylinker site
E) All of these

Question 32

If a PCR reaction begins using only one double stranded fragment of DNA,how many fragments will be produced after 12 cycles?

A) 2
B) 12
C) 256
D) 1024
E) 4096

Question 33

Which type of vector would be most effective for inserting a foreign piece of DNA that is 13kb in size into E.coli?

A) Plasmid
B) Bacteriophage
C) BAC
D) Cosmid
E) YAC

Question 34

The intragenic complementation between the amino terminal fragment of b-galactosidase and the defective DM15 polypeptide which permits the Xgal color test to be utilized without placing the entire lacZ gene in the pUC vectors is called:

A) Forced cloning
B) a-complementation
C) Blue/white color selection
D) In situ hybridization
E) Complementation screening

Question 35

A cosmid can best be described as a hybrid of:

A) A plasmid and a bacteriophage
B) A plasmid and a BAC
C) A bacteriophage and a phagemid
D) A phagemid and a BAC
E) None of these

Question 36

DNA molecules that are synthesized from an RNA template are known as:

A) cDNA molecules
B) sDNA molecules
C) gDNA molecules
D) rDNA molecules
E) All of these

Question 37

Which of the following is true about Taq polymerase?
1)It does not contain a built-in 3¢ ® 5¢ proofreading activity
2)It produces a higher than normal frequency of replication errors
3)It is derived from a bacteria known as Thermus aquaticus

A) 1
B) 2
C) 3
D) 1 and 3
E) All of these

Question 38

Which of the following is a disadvantage of the PCR process?

A) Fragments longer than 35kb cannot be efficiently amplified
B) It replicates double stranded DNA exponentially
C) It requires DNA to be denatured
D) All of these
E) None of these

Question 39

Which of the following statements about cosmid vectors is false?

A) They can accept DNA inserts of 35-45kb in size
B) They can replicate autonomously like a plasmid
C) Their DNA is packaged in the heads of lambda phage particles
D) They do not contain an origin of replication or a selectable marker gene
E) All of these

Question 40

Which of the following is an advantage that the cosmid vector possesses?
1)Can replicate autonomously in E.coli
2)Has the packaging capacity of lambda chromosome
3)Efficient transformation in E.coli

A) 1
B) 2
C) 3
D) 1 and 3
E) All of these

Question 41

How can site specific mutagenesis be conducted using PCR?

Question 42

Draw all of the DNA fragments that would result after 3 rounds of PCR if you start with: linear template DNA that is 2kb in length,two primers each of which have complementary sequences located 0.5 kb in from each end of the template and which are properly oriented for PCR,and all other components necessary for PCR.Label all DNA ends with regards to polarity and give fragment sizes where applicable.

Question 43

Describe the Sanger method of DNA sequencing.

Question 44

What is a restriction endonuclease? Name and give a drawing of the types of ends that can be produced after restriction enzyme digestion.Why are these enzymes named restriction endonucleases?

Question 45

A researcher is using gel electrophoresis to separate very small DNA fragments.What type of gel should the researcher use to perform this separation?

A) Agarose
B) Blood agar
C) Acrymalide
D) Agarose or Blood agar
E) All of these are appropriate

Question 46

When mutations are available in a gene of interest,the wild-type allele of the gene can be identified by a process called:

A) In vitro hybridization
B) Plaque hybridization
C) Southern hybridization
D) Complementation screening
E) In vitro packaging

Question 47

If you wanted to identify and characterize a protein in a cellular extract,which of the following techniques would you use?

A) Southern Blotting
B) Northern Blotting
C) Western Blotting
D) Southern Blotting and Western Blotting
E) All of these

Question 48

If you were constructing the first strand of a cDNA library,you would need all of the following except:

A) DNA Ligase
B) DNA template
C) RNA template
D) Poly-T oligomers
E) Reverse transcriptase

Question 49

What is the genetic sequence shown on the autoradiogram below?

A) AATGTCAGCCTT
B) TTCCGACTGTAA
C) AAATTTTCCCGG
D) GGCCCTTTTAAA
E) TTTAAAAGGGCC

Question 50

A physical map of a chromosome can be created by:

A) Mapping the restriction cleavage sites in the chromosome
B) Using electron microscopy
C) Using western blotting
D) Using recombination experiments
E) All of these

Question 51

Explain how genomic libraries are constructed and the two methods that are used to insert the DNA into the cloning vector.

Question 52

When pASH1 is digested by various restriction enzymes and combinations thereof,the following bands are observed.Construct a restriction enzyme map with this information.

Question 53

Which of the following techniques is most appropriate for analyzing RNA fragments?

A) Souther Blotting
B) Northern Blotting
C) RT-PCR
D) Southern Blotting and Northern Blotting
E) Northern Blotting and RT-PCR

Question 54

Which of the following is a method by which a gene can be isolated from a DNA library?

A) In situ colony hybridization
B) Genetic complementation
C) Genetic selection
D) In situ plaque hybridization
E) All of these

Question 55

Site specific mutagenesis is commonly and efficiently performed by which procedure?

A) PCR
B) Southern Blotting
C) Nothern Blotting
D) Western Blotting
E) Complementation Testing

Question 56

How is a Southern Blot performed and why does this technique provide more information than gel electrophoresis?

Question 57

All of the following enzymes are used in the construction of cDNA libraries,except:

A) Terminal transferase
B) Ribonuclease H
C) DNA polymerase I
D) DNA Ligase
E) Exonuclease