Filters
Question type

Study Flashcards

You try to generate a knockout mouse for a gene of interest, using the protocol described in this chapter. You do obtain progeny heterozygous for the knockout, as assessed by Southern blot. When you cross these heterozygous mice, you obtain viable progeny - some are heterozygous for the knockout, but none are found that are homozygous for the knockout. Which of following is the MOST likely explanation for this result?


A) The target gene was not disrupted successfully.
B) Genes in addition to the target gene were disrupted.
C) The heterozygous mice in your cross did not mate properly.
D) The target gene is haploinsufficient; that is, a mutant phenotype is observed when only one copy of the gene is disrupted.
E) The target gene is essential for viability.

Correct Answer

verifed

verified

All of the following are requirements of a bacterial cloning vector EXCEPT:


A) origin of replication.
B) unique restriction enzyme sites.
C) Ti plasmid.
D) selectable markers.

Correct Answer

verifed

verified

Which of the following remains a problem of gene therapy?


A) To date, there has not been a case of gene therapy curing a disease.
B) We have yet to develop a vector for delivering the gene.
C) Patients mount immune responses to the transferred gene and vectors.
D) We do not have the ability to use somatic gene therapy at this time.
E) We can only alter germ-line cells at this time.

Correct Answer

verifed

verified

You are examining a 1000-bp DNA fragment as part of a forensic analysis. If the limit of detection of this molecule is 9 × 108 molecules, what is the minimum number of PCR cycles you would have to run to detect a PCR product generated from a single molecule of the template?

Correct Answer

Answered by ExamLex AI

Answered by ExamLex AI

To determine the minimum number of PCR c...

View Answer

A pedigree and Southern blot results in humans are shown in the following figure. Filled-in figures represent individuals expressing a dominant trait (hypothetical) for blue tongue. What can you say about the potential linkage relationship between the allele responsible for the trait? Shaded regions within the homologs represent sequences that hybridize to the probe used for the Southern analysis. Arrows indicate cleavage sites used for the Southern analysis. A pedigree and Southern blot results in humans are shown in the following figure. Filled-in figures represent individuals expressing a dominant trait (hypothetical) for blue tongue. What can you say about the potential linkage relationship between the allele responsible for the trait? Shaded regions within the homologs represent sequences that hybridize to the probe used for the Southern analysis. Arrows indicate cleavage sites used for the Southern analysis.

Correct Answer

verifed

verified

Which of the following BEST describes knockout mice?


A) They have a gene of interest that has been fully disabled.
B) They have lower expression levels of a gene of interest.
C) They have higher expression levels of a gene of interest.
D) They have a point mutation in the gene of interest.
E) They have a gene removed, which results in lowered fertility.

Correct Answer

verifed

verified

Gel electrophoresis can be used to separate DNA on the basis of:


A) size.
B) electrical charge.
C) nucleotide content.
D) the probe used.
E) both size and electrical charge.

Correct Answer

verifed

verified

How might RNAi be used to treat diseases in humans?


A) siRNAs could be generated that would silence elevated levels of a harmful gene.
B) An RNAi library could be generated to assay harmful gene expression levels.
C) RNAi probes could bind to good genes and thus increase their expression.
D) RNAi could be used to amplify large amounts of therapeutic proteins.
E) RNAi cannot be used in humans, as it is a process found only in plants.

Correct Answer

verifed

verified

In the introduction to this chapter, the use of the CRISPR-Cas9 system to make a deletion of exon 23 containing a premature stop codon in mdx mice was described. The resulting mice had partially restored dystrophin protein and muscle function. Which of the following CRISRP-Cas9 mediated changes might lead to a better restoration of dystrophin protein and muscle function?


A) A deletion of exon 24 in addition to exon 23
B) A deletion of intron 23
C) A deletion of 30 bases within exon 23
D) A deletion of 25 bases within exon 21
E) An insertion of a corrected copy of exon 23 after the mutant exon 23

Correct Answer

verifed

verified

C

During gel electrophoresis, large DNA fragments will _____ small DNA fragments.


A) migrate more rapidly than
B) migrate at the same speed as
C) migrate more slowly than
D) cause degradation of
E) separate into

Correct Answer

verifed

verified

Use the following to answer questions You identify an RFLP in mice by digesting genomic DNA with HindIII enzyme and radiolabeling a piece of probe DNA. Southern blot analysis shows that the probe detects a 2-kb fragment in one strain of mice and a 4-kb fragment in another strain of mice. The two mice strains are crossed to produce an F1 generation. Two F1 siblings are mated to produce a dozen F2 progeny. You isolate genomic DNA from several F1 and F2 individuals, digest with HindIII, and perform a Southern blot with the same probe. -How many bands would be seen in the Southern blot of an F1 individual?


A) one
B) two
C) three
D) four
E) one or two

Correct Answer

verifed

verified

B

List two applications of recombinant DNA technology.

Correct Answer

Answered by ExamLex AI

Answered by ExamLex AI

Recombinant DNA technology, also known a...

View Answer

What is the function of dideoxynucleotides in Sanger DNA sequencing?


A) They act as primers for DNA polymerase.
B) They act as primers for reverse transcriptase.
C) They cut the sequenced DNA at specific sites.
D) They allow only the specific sequencing of the RNAs of a genome.
E) They stop synthesis at a specific site, so the base at that site can be determined.

Correct Answer

verifed

verified

E

The following are steps required to develop a knockout mouse. Place them in the CORRECT order.


A) 1, 4, 5, 6, 2, 3
B) 4, 1, 6, 5, 3, 2
C) 4, 5, 1, 6, 2, 3
D) 1, 4, 5, 2, 6, 3
E) 1, 6, 4, 5, 2, 3

Correct Answer

verifed

verified

A scientist edits a mammalian gene by changing a single AT base pair to a GC base pair. Which of the following methods might she have used to make this change? (Select all that apply.)


A) Site-directed mutagenesis
B) Oligonucleotide-directed mutagenesis
C) CRISPR-Cas9 genome editing followed by nonhomologous end joining (NHEJ)
D) CRISPR-Cas9 genome editing followed by homologous recombination (HR) with a donor template
E) Mutagenesis with radiation

Correct Answer

verifed

verified

You are interested in a particular segment of rhinoceros DNA and would like to clone it into a cloning plasmid. You have the following restriction map of the region that includes the DNA of interest and the plasmid (E = EcoRI, H = HindIII, X = XbaI, S = SphI, N = NotI) . You are interested in a particular segment of rhinoceros DNA and would like to clone it into a cloning plasmid. You have the following restriction map of the region that includes the DNA of interest and the plasmid (E = EcoRI, H = HindIII, X = XbaI, S = SphI, N = NotI) .   Which restriction enzymes would you choose to clone the DNA of interest into the cloning vector? A)  E and H B)  S C)  X and N D)  S and N Which restriction enzymes would you choose to clone the DNA of interest into the cloning vector?


A) E and H
B) S
C) X and N
D) S and N

Correct Answer

verifed

verified

Which of the following statements is NOT correct?


A) Coding sequences for gene products can be isolated from cDNA libraries.
B) Antibodies are used for Northern blot analysis.
C) The number of STR copies is variable throughout human populations.
D) PCR amplification generates large numbers of linear DNA fragments.
E) RNA molecules can be used as hybridization probes in Southern blot analysis.

Correct Answer

verifed

verified

Cloned eukaryotic genes are not always able to be expressed in bacterial cells. What are some possible reasons for this?

Correct Answer

Answered by ExamLex AI

Answered by ExamLex AI

Cloned eukaryotic genes often face sever...

View Answer

Suppose you have previously located and cloned a human gene on chromosome 2. You now believe there is an important disease-related gene nearby on the same chromosome. What technique might you employ to locate the disease-related gene?


A) chromosome walking
B) DNA fingerprinting
C) site-directed mutagenesis
D) RNAi
E) CRISPR-Cas genome editing

Correct Answer

verifed

verified

Which of the following statements is NOT true regarding the basic components required for a bacterial cloning vector?


A) Selectable markers provide a means for preferentially allowing growth of only those bacterial cells that have been transformed with the cloning vector.
B) Unique restriction enzyme sites allow for larger pieces of foreign DNA to be inserted into the bacterial cloning vector.
C) Unique restriction enzyme sites provide a means for inserting the foreign DNA into the cloning vector at a specific known sequence site.
D) A bacterial origin of replication ensures that the plasmid is replicated while present within the bacterial cell.
E) Selectable markers provide a means for selecting cells that have been transformed with a recombinant plasmid.

Correct Answer

verifed

verified

Showing 1 - 20 of 72

Related Exams

Show Answer