Chapter 14 quiz

Sanger's original DNA sequencing method differs from current automated DNA sequencing methods because (multiple answers): A) Automated methods use a single polymerase reaction tube B) automated methods use fluorescently labelled ddNTPs C) automated methods use agarose gel electrophoresis with a laser readout D) automated methods do not use autoradiographs E) automated methods analyze color, not size of fragments

A) Automated methods use a single polymerase reaction tube B) automated methods use fluorescently labelled ddNTPs D) automated methods do not use autoradiographs

Match the terms provided with the best choice: A) Cloning vector B) expression vector C) transgene D) selectable marker E) restriction enzyme F) ddNTP antibiotic resistance protein plasmid cohesive end sanger sequencing foreign DNA

A) Cloning vector- plasmid B) expression vector- protein C) transgene- foreign DNA D) selectable marker- antibiotic resistance E) restriction enzyme- cohesive end F) ddNTP-Sanger sequencing

A target gene can be identified in a complex mixture of DNA fragments by southern blot using: A) DNA or RNA radioactive probes that are complementary to the gene of interest B) Primers and Taq polymerase to amplify the gene C) antibodies specific for the protein product of the gene D) DNA or RNA probes complementary to the selectable marker used for cloning E) all of the above

A) DNA or RNA radioactive probes that are complementary to the gene of interest

A DNA probe with a sequence similar to that of the gene of interest is often used to screen a DNA library. What could you use as a probe if the sequence of the gene of interest is not known? A) a similar gene from another organism B) a synthetic probe based on a restriction enzyme site C) an antibody D) this screen is not possible until the DNA sequence of the gene of interest is known

A) a similar gene from another organism

You have found a mutant form of frog that is orange and you now want to find the gene that caused this color change. This type of analysis is called: A) forward genetics B) reverse genetics C) transgenic mouse models D) knockout mice

A) forward genetics

Which procedure of modern genetic analysis allows for the most direct determination of the function of a gene? A) targeted gene knockout B) transgenesis C) genetic dissection D) gene sequencing E) gene cloning

A) targeted gene knockout

DNA libraries are constructed and screened for genes of interest. If you were interested in identifying genes expressed in cancer cells, why might you choose to use a cDNA library instead of a genomic DNA library? A) A cDNA library is larger (in quantity) than a genomic library is B) a cDNA library is enriched for genes that are actively transcribed in your cell of interest C) a cDNA library is enriched with noncoding DNA D) a cDNA library is enriched for genes that are expressed at low frequency E) all of the above

B) a cDNA library is enriched for genes that are actively transcribed in your cell of interest

A selectable marker is needed after bacterial transformation with plasmids to: A) ensure the plasmid is inserted into the bacterial DNA B) find the small percentage of bacteria will take up the plasmid C) facilitate the transcription of the target gene D) kill the bacteria that are transformed by the plasmid E) ensure the protein from the target gene is properly expressed in the bacteria

B) find the small percentage of bacteria will take up the plasmid

Positional cloning relies on: A) pedigrees B) information about a mapped gene that co-segregates with the trait (gene) of interest C) computerized DNA data mining D) random cloning of chromosomal DNA E) random cloning of chromosomal DNA and probing with DNA complementary to a known amino acid sequence

B) information about a mapped gene that co-segregates with the trait (gene) of interest

When present in small amounts in sequencing reactions, dideoxyribonucleoside triphosphates (ddNTPs) terminate the sequencing reaction at different positions in the growing DNA strands. ddNTPs stop a sequencing reaction because they: A) lack a 5' phosphate group B) have a hydroxyl group at their 5' end C) lack a hydroxyl (OH-) group at their 3' end D) permanently bind to the active site of the DNA polymerase E) cause DNA polymerase to fall off the template strand

C) lack a hydroxyl (OH-) group at their 3' end

Gene therapy has had limited success to date because: A) most genetic diseases have multiple genes that are mutated B) current regulations prevent experimentation in humans C) some human trials resulted in insertion of the gene of interest into a location that caused cancer D) there are no methods to deliver DNA into human cells E) you need a good immune response to the corrected gene product for it to be effective

C) some human trials resulted in insertion of the gene of interest into a location that caused cancer

Expression vectors differ from cloning vectors because: A) they make viruses B) they are not used for gene therapy C) they contain promoters and regulatory elements for transcription and translation of protein D) they are used for cloning PCR products E) they have a bacterial origin of replication

C) they contain promoters and regulatory elements for transcription and translation of protein

Restriction enzymes that make blunt cuts of DNA are not usually used for cloning DNA into a vector because: A) they cut DNA into too many pieces B) they usually only recognize 4 bp sequences C) they do not leave DNA overhangs to aid in joining the foreign DNA to the vector DNA D) the plasmid vectors do not have these restriction sites E) blunt cut DNA cannot be ligated together

C) they do not leave DNA overhangs to aid in joining the foreign DNA to the vector DNA

To clone a very large piece of DNA (over 100,000 base pairs), which of the following bacterial cloning vectors should be used? A) plasmid B) phage lambda C) cosmid D) bacterial artificial chromosome E) all of the above can be used to clone any size DNA

D) bacterial artificial chromosome

Restriction fragment length polymorphism (RELP) is a technique used to map genes. RFLP takes advantage of variations in the pattern of fragments produced by restriction enzymes. What types of mutations will cause fragment pattern differences? A) single-base mutations that occur randomly anywhere in the genome B) mutations will not cause pattern differences C) mutations that affect gene expression D) only mutations that occur at restriction sites in the genome

D) only mutations that occur at restriction sites in the genome

Restriction fragment length polymorphisms: A) can be linked to pedigrees to help identify mutant genes B) can be used for crime scene investigations C) require 10 or more nucleotide substitutions to be useful D) do not use DNA that has been amplified by PCR E) A and B

E) A and B

You are studying a human gene encoding a protein that requires posttranslational modification. What feature(s) is important in picking your vector if you want to study mutations that affect protein function? A) it needs to be an expression vector B) it needs to be a vector that can replicate in eukaryotic cells C) it does not require a selection marker D) it must be able to integrate into a chromosome of the transformed cell E) Both a and b

E) Both a and b

Cloning of genes into bacterial plasmids is useful to: A) obtain a large number of copies of the gene of interest B) translate the protein product of the gene of interest to study its function C) be able to make mutations in the gene of interest D) perform sequence analysis of the gene of interest E) all of the above

E) all of the above

During gel electrophoresis _______ will migrate more rapidly than ________ A) large DNA fragments, cloning vectors B) ethidium bromide, cloning vectors C) large DNA fragments, small DNA fragments D) small DNA fragments, DNA size markers E) small DNA fragments, large DNA fragments

E) small DNA fragments, large DNA fragments

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

E) they stop synthesis at a specific site so the base at that site can be determined