Deck 11: DNA Technology

Question 1

In Figure 11.6, the first 10 bases of the DNA strand being sequenced are:

A)5'-GTGAATGCGT-3'.
B)5'-TACATCGTGC-3'.
C)3'-GTGAATGCGT-5'.
D)3'-TACATCGTGC-5'.
E)3'-ACGCATTCAC-5'.

Answer 1

5'-GTGAATGCGT-3'.

Question 2

A virgin was raped in Los Angeles and became pregnant.Police investigations have identified four suspects.The woman decided to go through with the pregnancy for religious reasons.It was possible to isolate a few cells of fetal origin from the maternal blood.Enough DNA was obtained for one polymerase chain reaction (PCR).The results for one microsatellite are shown in the gel image in Figure 11.1.Lane 1 is the mother's DNA, lane 2 is the fetal DNA, and lanes 3 to 6 are the suspect's DNA.Which of the suspects remain suspects after this analysis?

A)3 and 5.
B)3 and 4.
C)6.
D)5 and 6.
E)4, 5, and 6.

Answer 2

4, 5, and 6.

Question 3

In the following dot blot, the probe used in the upper row is for the normal sequence while the probe in the second row is for the -Phe mutation of the cystic fibrosis gene.What are the genotypes of the four people investigated?

A)Normal; affected; heterozygote; normal.
B)Affected; normal; heterozygote; affected.
C)Normal; heterozygote; affected; normal.
D)Affected; affected; heterozygote; normal.
E)Heterozygote; affected; heterozygote; heterozygote.

Answer 3

Normal; affected; heterozygote; normal.

Question 4

PCR and DNA sequencing differ in which of the following requirements?

A)DNA polymerase.
B)An oligonucleotide primer.
C)Deoxynucleoside triphosphates.
D)DNA template.
E)Dideoxynucleoside triphosphates

Question 5

Figure 11.5 is an image of a gel electrophoresis pattern of a microsatellite.The samples are random blood samples from New York, and alleles containing 7, 12, 20, 22, and 35 repeat units can be seen in this gel.Which fragment corresponds to the allele containing 35 repeats?

A)No.1.
B)No.2.
C)No.3.
D)No.4.
E)No.5.

Question 6

Many oncogenic mutations change the rate at which cellular genes are expressed.All of the following methods can be used to compare the gene expression profiles of cancer cells with those of the normal cells from which they are derived, except:

A)Southern blot.
B)Western blot.
C)A DNA microarray.
D)Northern blot.
E)An immunological test that uses antibodies in order to detect proteins.

Question 7

The binding of an oligonucleotide probe to a specific sequence of DNA is influenced by which of the following:

A)Temperature, salt concentration, nucleotide sequence, and radioactivity only.
B)Temperature, salt concentration, pH, and nucleotide sequence only.
C)Temperature, salt concentration, and nucleotide sequence only.
D)Temperature, nucleotide sequence, and pH only.
E)Temperature and nucleotide sequence only.

Question 8

The following Southern blot was performed to examine a mutation that is linked to a genetic disease.The blot was probed with fluorescent-labeled cDNA of the gene.What is the most likely explanation for the abnormal bands in the patient in comparison with the normal control?

A)Faulty splicing of the messenger RNA (mRNA).
B)The deletion of an entire exon.
C)A single-nucleotide polymorphism.
D)Duplication of at least one exon.
E)The expansion of a microsatellite.

Question 9

Lane 1 in the following Southern blot contains a sample from a normal control, and lane 2 contains a sample from a patient.The arrow indicates the location of the wells in the agarose gel used in this analysis.The probe used was a complementary DNA (cDNA).Which type of mutation is most likely, on the basis of these data?

A)Point mutation that changes a codon encoding glutamic acid into a stop-codon.
B)Deletion of part of one exon.
C)A single-nucleotide polymorphism that has eliminated a restriction site.
D)Duplication of three exons.
E)Deletion of the entire gene.

Question 10

Which of the following is the most plausible recognition site for a restriction endonuclease?

A)A A G C T T.
B)C G A A G C.
C)T G C T G C.
D)A A G G C C.
E)T A C G T A.

Question 11

Lane 1 in the following Southern blot contains a sample from a normal control, and lane 2 contains a sample from a patient.The probe is based on the cDNA of a gene.Which type of mutation is most likely, on the basis of these data?

A)Point mutation changing an amino acid coding codon into a stop codon.
B)Insertion of an Alu sequence.
C)Duplication of three exons.
D)Deletion of the entire gene.
E)Deletion of part of one exon.

Question 12

RNA interference can be used for experimental and possibly therapeutic purposes.RNA interference is triggered by:

A)Shortening of telomeres in aging cells.
B)Activation of oncogenes in malignant cells.
C)Exposure to viral spike proteins.
D)Double-stranded RNA molecules.
E)DNA-RNA hybrid molecules.

Question 13

The most important "selectable markers" used in recombinant DNA technology with bacteria are:

A)Self-transmissible plasmid, such as the F factor.
B)Single-stranded cloning vectors that are used for DNA sequencing.
C)Genes for integrase enzymes that are needed for the integration of recombinant DNA in the bacterial genome.
D)Bacteriophages that carry a foreign DNA.
E)Genes for antibiotic resistance that permit the selective survival of engineered bacteria.

Question 14

What are loxP sites, and for which purpose are they used?

A)Cleavage sites for a class of restriction endonucleases that are popular for recombinant DNA studies.
B)Recombination sites that are recognized by a Cre recombinase, used for the targeted excision of genes.
C)Integration sites for retroviral vectors that are used for targeted gene insertion.
D)Sites on RNA that are the target of a selective RNase, used to suppress the expression of genes selectively.
E)Hot spots for homologous recombination, used to introduce genes into the genome by homologous recombination.

Question 15

In the following family, I-2 and II-1 have died from a rare form of colon cancer that is inherited as an autosomal dominant trait.The remaining family members have undergone genotyping for a microsatellite marker close to the known gene for colon cancer susceptibility.According to this analysis, what are the genotypes of the children in the third generation (left to right; the term carrier is used for a person who has the genetic disposition but has not yet developed the disease)?

A)Carrier, normal, carrier, normal.
B)Carrier, normal, normal, carrier.
C)Normal, carrier, normal, carrier.
D)Normal, carrier, carrier, normal.
E)Normal, carrier, normal, normal.