Nadia Siddique
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Quiz sobre Molecular Genetics, criado por Nadia Siddique em 17-01-2016.

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Nadia Siddique
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Molecular Genetics

Questão 1 de 74

1

The first step in the polymerase chain reaction (PCR) is

Selecione uma das seguintes:

  • Denaturation

  • Cooling

  • Annealing

  • Primer extension

Explicação

Questão 2 de 74

1

In a polymerase chain reaction, a synthetic sequence of nucleotides are involved in

Selecione uma das seguintes:

  • Denaturing

  • Heating

  • Cooling

  • Copying

  • All of the above

Explicação

Questão 3 de 74

1

Bacteria protect themselves from viruses by fragmenting viral DNA upon entry with

Selecione uma das seguintes:

  • Ligases

  • Endonucleases

  • Methylases

  • Vectors

  • Probes

Explicação

Questão 4 de 74

1

When "sticky ends" are paired, they can be joined by

Selecione uma das seguintes:

  • Restriction Enzymes

  • pSC101

  • Methylases

  • X-gal

  • DNA ligase

Explicação

Questão 5 de 74

1

One of the most useful methods for identifying a specific gene is

Selecione uma das seguintes:

  • Western blot

  • Southern blot

  • Eastern blot

  • Magnetic resonance imaging

  • Thin chromatography

Explicação

Questão 6 de 74

1

The Polymerase Chain Reaction is used to:

Selecione uma das seguintes:

  • amplify a small amount of DNA

  • cleave bacterial plasmids

  • seal "sticky ends"

  • identify target plasmids

  • none of the above

Explicação

Questão 7 de 74

1

When tryptophan is present in the medium, the transcription of tryptophan producing genes in E. coli is stopped by a helix-turn-helix regulator binding to the

Selecione uma das seguintes:

  • trp repressor

  • trp operon

  • trp promoter

  • trp operator

  • trp polymerase

Explicação

Questão 8 de 74

1

When tryptophan is present in the environment of E. coli, the tryptophan binds to the

Selecione uma das seguintes:

  • trp operon

  • trp promoter

  • trp operator

  • trp repressor

  • trp polymerase

Explicação

Questão 9 de 74

1

The operon that controls tryptophan producing genes in E. coli consists of _______________

Selecione uma das seguintes:

  • activator

  • regulator

  • promoter

  • operator

  • repressor

Explicação

Questão 10 de 74

1

In order for a gene to be transcribed, RNA polymerase must have access to the DNA helix and be able to bind to the genes

Selecione uma das seguintes:

  • activator

  • regulator

  • promoter

  • operator

  • repressor

Explicação

Questão 11 de 74

1

In the function of the lac operon in E. coli, the lac genes are transcribed in the presence of lactose because

Selecione uma das seguintes:

  • RNA polymerase binds to the operator

  • the repressor cannot bind to the promoter

  • an isomer of lactose binds to the repressor

  • CAP does not bind to the operator

  • of the absence of cAMP

Explicação

Questão 12 de 74

1

The role of methylation of DNA is now viewed as

Selecione uma das seguintes:

  • interfering with DNA transcription by blocking base pairing between cytosine and guanine

  • complexing with enhancers to prevent transcription

  • prevention of mutation

  • insuring that genes that are turned off, stay off

  • irrelevant to gene transcription

Explicação

Questão 13 de 74

1

E. coli is able to use foods other than glucose in the absence of available glucose, because falling levels of glucose cause an increase of

Selecione uma das seguintes:

  • cAMP

  • CAP

  • lactase

  • glu operon

  • tRNA

Explicação

Questão 14 de 74

1

In the absence of glucose, E. coli can import lactose to change into glucose and galactose because CAP binds to the

Selecione uma das seguintes:

  • cAMP

  • DNA

  • lac operon

  • operator

  • repressor

Explicação

Questão 15 de 74

1

Which is not part of the lac operon?

Selecione uma das seguintes:

  • repressor

  • activator protein

  • operator

  • promoter

  • structural gene

Explicação

Questão 16 de 74

1

In an operon the location of the regulatory region occurs ________ the structural genes.

Selecione uma das seguintes:

  • after

  • within

  • before

Explicação

Questão 17 de 74

1

Which of the following is part of an operon?

Selecione uma das seguintes:

  • structural genes

  • operator

  • promoter

  • a CAP binding site

  • all of the above

Explicação

Questão 18 de 74

1

Transcription is initiated when RNA polymerase binds to

Selecione uma das seguintes:

  • promoter

  • initiator

  • codon

  • transcriptor

Explicação

Questão 19 de 74

1

In eukaryotes, there are _______________ codons that specify amino acids

Selecione uma das seguintes:

  • 21

  • 24

  • 61

  • 64

  • 100

Explicação

Questão 20 de 74

1

In eukaryotes, the "start" codon also specifies the amino acid,

Selecione uma das seguintes:

  • phenylalanine

  • valine

  • methionine

  • aspartate

Explicação

Questão 21 de 74

1

In transcription, the nucleotide sequence CAT in DNA would specify _______________ in mRNA.

Selecione uma das seguintes:

  • TAC

  • GAU

  • CAT

  • GTU

  • GUA

Explicação

Questão 22 de 74

1

The genetic code consists of groups of three nucleotides called

Selecione uma das seguintes:

  • codons

  • introns

  • anticodons

  • reading frame

  • triplets

Explicação

Questão 23 de 74

1

The function of tRNA is to

Selecione uma das seguintes:

  • provide a site for polypeptide synthesis

  • transport amino acids to the ribosome

  • travel to the ribosome to direct the assembly of polypeptides

  • transcribe DNA

  • translate DNA

Explicação

Questão 24 de 74

1

In the formation of an initiation complex, a _______________ is positioned first.

Selecione uma das seguintes:

  • met-tRNA

  • ser-tRNA

  • tyr-rRNA

  • mval-tRNA

  • cyst-tRNA

Explicação

Questão 25 de 74

1

The function of mRNA is to

Selecione uma das seguintes:

  • provide a site for polypeptide synthesis

  • transport amino acids to the ribosome

  • travel to the ribosome to direct the assembly of polypeptides

  • transcribe DNA

  • translate DNA

Explicação

Questão 26 de 74

1

The process of _______________ cuts introns from the primary transcript and the final "processed" mRNA is produced.

Selecione uma das seguintes:

  • RNA cleaving

  • RNA translocation

  • RNA splicing

  • RNA elongation

  • RNA releasing

Explicação

Questão 27 de 74

1

In the process of translation,

Selecione uma das seguintes:

  • a strand of mRNA is formed with nucleotide sequences complementary to those of DNA

  • nucleotide sequences of tRNA are established

  • a polypeptide is formed in response to the rRNA nucleotide sequence

  • rRNA is synthesized with sequences complementary to those of tRNA

  • a polypeptide is formed as dictated by the nucleotide sequence in mRNA

Explicação

Questão 28 de 74

1

In mRNA, the series of nucleotides CCC specifies

Selecione uma das seguintes:

  • serine

  • proline

  • alanine

  • arginine

  • stop

Explicação

Questão 29 de 74

1

A molecule of tRNA with the anticodon AAA will transport the amino acid

Selecione uma das seguintes:

  • phenylalanine

  • lysine

  • glycine

  • leucine

  • alanine

Explicação

Questão 30 de 74

1

As polypeptides are formed at the ribosome, elongation continues until _______________ is exposed.

Selecione uma das seguintes:

  • a release factor

  • an intron

  • a nonsense codon

  • an exon

  • polypeptidases

Explicação

Questão 31 de 74

1

Which one of the following is not a kind of RNA?

Selecione uma das seguintes:

  • mRNA

  • tRNA

  • rRNA

  • nRNA

  • All of the above are kinds of RNA

Explicação

Questão 32 de 74

1

The direct result of transcription is

Selecione uma das seguintes:

  • a duplicate DNA molecule

  • nRNA

  • protein

  • mRNA

  • none of the above

Explicação

Questão 33 de 74

1

The direct result of translation is

Selecione uma das seguintes:

  • duplicate DNA

  • mRNA

  • protein

  • nRNA (nuclear RNA)

  • none of the above

Explicação

Questão 34 de 74

1

Which one of the following is not associated with transcription?

Selecione uma das seguintes:

  • tRNA

  • mRNA

  • nRNA

  • rRNA

  • all of the above

Explicação

Questão 35 de 74

1

Which one of the following is not associated with translation?

Selecione uma das seguintes:

  • tRNA

  • mRNA

  • rRNA

  • anticodons

  • All are involved with translation

Explicação

Questão 36 de 74

1

According to Chargaff's rule, the following proportion exists in DNA

Selecione uma das seguintes:

  • A=G

  • C=G

  • T=G

  • A>T

  • C>G

Explicação

Questão 37 de 74

1

The actual synthesis of DNA in E. coli is the function of

Selecione uma das seguintes:

  • polymerase I

  • primase

  • primer

  • polymerase III

  • ligase

Explicação

Questão 38 de 74

1

Since the first nucleotides cannot be linked in a newly synthesized strand in DNA replication, ___________ is required.

Selecione uma das seguintes:

  • DNA primer

  • DNA ligase

  • DNA polymerase

  • RNA primer

  • helicase

Explicação

Questão 39 de 74

1

The fact that some viruses use DNA to direct their heredity was demonstrated by

Selecione uma das seguintes:

  • finding radioactive sulfur from a bacteriophage in a bacterium

  • finding radioactive phosphorus from a bacterium in a bacteriophage

  • finding that radioactive phosphorus from a bacteriophage had mutated in bacterium

  • finding radioactive phosphorus from a bacteriophage in a bacterium

  • finding radioactive sulfur from a bacterium in a bacteriophage

Explicação

Questão 40 de 74

1

Okazaki fragments are used to elongate

Selecione uma das seguintes:

  • the leading strand toward the replication fork

  • the lagging strand toward the replication fork

  • both strands in both directions

  • the leading strand away from the replication fork

  • the lagging strand away from the replication fork

Explicação

Questão 41 de 74

1

In nucleic acids, the free hydroxyl group is attached to the _______________ carbon of the sugar.

Selecione uma das seguintes:

  • 5'

  • 4'

  • 3'

  • 2'

  • 1'

Explicação

Questão 42 de 74

1

A single enzyme is specified by a single

Selecione uma das seguintes:

  • gene

  • chromosome

  • nucleosome

  • nucleotide

  • histone

Explicação

Questão 43 de 74

1

In replication of DNA, the helix is opened and untwisted by

Selecione uma das seguintes:

  • ribase

  • primase

  • deoxase

  • helicase

  • ligase

Explicação

Questão 44 de 74

1

_______________ join DNA fragments to the lagging strand

Selecione uma das seguintes:

  • telomeres

  • centromeres

  • helicases

  • ligases

  • polymerases

Explicação

Questão 45 de 74

1

Which statement about the elongation of the lagging strand during DNA replication is correct?

Selecione uma das seguintes:

  • It is synthesized in a 3' --> 5' direction.

  • It progresses (grows) toward the replication fork

  • It requires a short RNA primer to proceed.

  • It is synthesized by DNA ligase

  • It is synthesized continuously

Explicação

Questão 46 de 74

1

If one side of a DNA molecule contains the following sequence of nucleotides, AGTCCG, the complementary sequence on the other side would be:

Selecione uma das seguintes:

  • GCCTGA

  • AGTCCG

  • TCAGGC

  • CTGAAT

  • none of the above

Explicação

Questão 47 de 74

1

During your summer job at Virotech, you isolate a previously unknown virus. Analysis of its genome reveals that it is composed of a double stranded DNA molecule containing 14% T (thymine). Based on this information, what would you predict the %C (cytosine) to be?

Selecione uma das seguintes:

  • 14%

  • 28%

  • 36%

  • 72%

  • can't tell!

Explicação

Questão 48 de 74

1

The process of acquiring a gene from another organism is called transformation.

Selecione uma das opções:

  • VERDADEIRO
  • FALSO

Explicação

Questão 49 de 74

1

The Hershey-Chase experiment showed that the virus protein is responsible for directing the production of new viruses.

Selecione uma das opções:

  • VERDADEIRO
  • FALSO

Explicação

Questão 50 de 74

1

The two sides of the double helix structure of DNA are held together with hydrogen bonds.

Selecione uma das opções:

  • VERDADEIRO
  • FALSO

Explicação

Questão 51 de 74

1

DNA replication is called semiconservative because half of each of the two new strands of DNA is "old" DNA from the original DNA molecule and half is "new" DNA.

Selecione uma das opções:

  • VERDADEIRO
  • FALSO

Explicação

Questão 52 de 74

1

Genetic engineering has been used to do all of the following except:

Selecione uma das seguintes:

  • make plants more resistant to frost

  • make plants more resistant to disease

  • make plants more resistant to herbicides

  • improve the nutritional balance of plants

  • all of the above

Explicação

Questão 53 de 74

1

According to Mendel, which of the following cause an organism's size, colour and markings?

Selecione uma das seguintes:

  • Chromosomes

  • Genes

  • Alleles

  • Factors

Explicação

Questão 54 de 74

1

Which term is associated with eukaryotic DNA?

Selecione uma das seguintes:

  • chrosome

  • histone

  • telomere

  • all of the above

Explicação

Questão 55 de 74

1

If 28% of a segment of DNA is composed of guanine, how much of the segment is adenine?

Selecione uma das seguintes:

  • 7%

  • 22%

  • 28%

  • There is no way to determine this.

Explicação

Questão 56 de 74

1

How did the work of Franklin and Wilkins contribute to the discovery of the structure of DNA?

Selecione uma das seguintes:

  • They determined the rule of base pairing

  • They determined that DNA has an X shape

  • They determined the double helix structure

  • They determined that the strands run antiparallel

Explicação

Questão 57 de 74

1

Which of these findings made Watson and Crick confident that their DNA model was correct?

Selecione uma das seguintes:

  • Chargaff's base-pairing ratios

  • Pauling's three-strand model

  • Franklin's early disagreement with the double helix theory

  • All of the above

Explicação

Questão 58 de 74

1

What would have been the results of Meselson and Stahl's experiment if DNA had undergone conservative replication?

Selecione uma das seguintes:

  • one band containing only 14N

  • one band containing only 15N

  • two bands: one of 15N and 14N

  • three bands: one of 15N, one of 14N, and one of 1:1 14N:15N

Explicação

Questão 59 de 74

1

Which characteristics of the structure of DNA results in a lagging strand and a leading strand during DNA replication?

Selecione uma das seguintes:

  • its phosphate backbone

  • its antiparallel strands

  • the ratio of purines to pyrimidines

  • the full twist every ten nucleotides

Explicação

Questão 60 de 74

1

What is the function of DNA ligase in replication?

Selecione uma das seguintes:

  • It initiates a replication bubble

  • It prevents DNA strands from tangling

  • It places nucleotides to form a new DNA strand

  • It fills gaps on the lagging strand

Explicação

Questão 61 de 74

1

Which method do prokaryotes use to compact DNA?

Selecione uma das seguintes:

  • Spooling around a histone

  • Forming a nucleosome

  • Supercoiling

  • Winding into solenoids

Explicação

Questão 62 de 74

1

Where are telomeres located?

Selecione uma das seguintes:

  • At ends of chromosomes

  • On the leading strand

  • At the replication fork

  • On prokaryotic plasmids

Explicação

Questão 63 de 74

1

What is the name of Beadle and Tatum's original hypothesis?

Selecione uma das seguintes:

  • One gene-one sequence hypothesis

  • One gene-one enzyme hypothesis

  • One gene-one peptide hypothesis

  • One gene-one polypeptide hypothesis

Explicação

Questão 64 de 74

1

What is the sequence of information transfer, as outlined by the central dogma?

Selecione uma das seguintes:

  • DNA -> tRNA -> mRNA --> polypeptide

  • DNA -> mRNA -> tRNA --> polypeptide

  • DNA -> mRNA -> rRNA --> polypeptide

  • DNA -> rRNA -> tRNA --> polypeptide

Explicação

Questão 65 de 74

1

Where is the TATA box found?

Selecione uma das seguintes:

  • In the termination sequence that stops DNA polymerase

  • In the termination sequence that stops RNA polymerase

  • In the promoter that enables the binding of DNA polymerase

  • In the promoter that enables the binding of RNA polymerase

Explicação

Questão 66 de 74

1

What happens during capping and tailing?

Selecione uma das seguintes:

  • A methyl 5' tail and poly(A) cap are added

  • A methyl 3' tail and poly(A) cap are added

  • A methyl 5' cap and poly(A) tail are added

  • A methyl 3' cap and poly(A) tail are added

Explicação

Questão 67 de 74

1

How is the lac operon inhibited?

Selecione uma das seguintes:

  • The lac repressor is not synthesized by the lacl gene

  • RNA polymerase is inhibited by high concentrations of allolactase

  • The lac repressor is inhbited by high concentrations of allolactase

  • Allolactase is not present to bind with the lac repressor

Explicação

Questão 68 de 74

1

Which term refers to a point mutation that results in a different amino acid in a particular position?

Selecione uma das seguintes:

  • Missense mutation

  • Silent mutation

  • Nonsense mutation

  • Frameshift mutation

Explicação

Questão 69 de 74

1

What is the molecular tool scientists use to cut a DNA fragment from a larger piece of DNA?

Selecione uma das seguintes:

  • Restriction enzymes

  • DNA primase

  • Methylase

  • DNA ligase

Explicação

Questão 70 de 74

1

After excising a DNA fragment that contains a target gene, what should a molecular biologist do?

Selecione uma das seguintes:

  • Introduce a vector into a suitable organism

  • Isolate a desired gene or DNA fragment

  • Select the transformed cells

  • Insert the gene into a vector

Explicação

Questão 71 de 74

1

Which chemical compound can be used to stain a completed electrophoresis gel?

Selecione uma das seguintes:

  • Ethidium bromide

  • Loading dye

  • Molecular marker

  • DNA polymerase

Explicação

Questão 72 de 74

1

During PCR, double-stranded DNA is separated into two single strands of DNA. What is this step called?

Selecione uma das seguintes:

  • Splicing

  • Denaturation

  • Extension

  • Annealing

Explicação

Questão 73 de 74

1

After 8 PCR cycles, how many target sequences have been synthesized?

Selecione uma das seguintes:

  • 8

  • 16

  • 240

  • 256

Explicação

Questão 74 de 74

1

How does genetic therapy differ from traditional methods of treating a disease?

Selecione uma das seguintes:

  • It targets the effects of the disease

  • In some cases, it fixes the genetic code itself

  • It reverses the damage done to the body

  • It replaces the need for organ transplant

Explicação