Question 1

What is the function of dideoxynucleotides in Sanger DNA sequencing?

Accepted Answer

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. 
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. E

Question 2

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 FS1U1B11S1U1B0 generation. Two FS1U1B11S1U1B0 siblings are mated to produce a dozen FS1U1B12S1U1B0 progeny. You isolate genomic DNA from several FS1U1B11S1U1B0 and FS1U1B12S1U1B0 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?

Accepted Answer

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

Question 3

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?

Accepted Answer

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 
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 C

Question 4

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

Accepted Answer

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

Question 5

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?

Accepted Answer

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. 
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.

Question 6

Which of the following statements is NOT correct?

Accepted Answer

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. 
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.

Question 7

How might RNAi be used to treat diseases in humans?

Accepted Answer

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. 
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.

Question 8

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

Accepted Answer

Cloned eukaryotic genes often face sever

Question 9

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?

Accepted Answer

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

Question 10

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

Accepted Answer

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

Question 11

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.)

Accepted Answer

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 
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

Question 12

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

Accepted Answer

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 
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

Question 13

Which of the following BEST describes knockout mice?

Accepted Answer

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. 
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.

Question 14

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

Accepted Answer

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. 
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.

Question 15

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

Accepted Answer

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

Question 16

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?

Accepted Answer

To determine the minimum number of PCR c

Question 17

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?

Accepted Answer

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

Question 18

Which of the following remains a problem of gene therapy?

Accepted Answer

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. 
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.

Question 19

List two applications of recombinant DNA technology.

Accepted Answer

Recombinant DNA technology, also known a

Question 20

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.

Accepted Answer

The answer of A pedigree and Southern blot results in...

Exam 19: Molecular Genetic Analysis and Biotechnology

What is the function of dideoxynucleotides in Sanger DNA sequencing?

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

Which of the following statements is NOT correct?

How might RNAi be used to treat diseases in humans?

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

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?

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

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.)

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

Which of the following BEST describes knockout mice?

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

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

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?

Which of the following remains a problem of gene therapy?

List two applications of recombinant DNA technology.

Introduction to Genetics

Chromosomes and Cellular Reproduction

Basic Principles of Heredity

Sex Determination and Sex-Linked Characteristics

Extensions and Modifications of Basic Principles

Pedigree Analysis, Applications, and Genetic Testing

Linkage, Recombination, and Eukaryotic Gene Mapping

Chromosome Variation

Bacterial and Viral Genetic Systems

DNA: the Chemical Nature of the Gene

Chromosome Structure and Organelle Dna

DNA Replication and Recombination

Transcription

Rna Molecules and Rna Processing

The Genetic Code and Translation

Control of Gene Expression in Prokaryotes

Control of Gene Expression in Eukaryotes

Gene Mutations and Dna Repair

Genomics and Proteomics

Epigenetics

Developmental Genetics and Immunogenetics

Cancer Genetics

Quantitative Genetics

Population Genetics

Evolutionary Genetics

Filters

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?