EXAM 4: QUIZ METHODS: GENES Flashcards
True or false: Restriction nucleases recognize specific sequences on single-stranded DNA.
f
A nuclease hydrolyzes the 22 bonds in a nucleic acid.
phosphodiester
True or false: The sizes of the fragments left after a restriction digest do not depend on the total size of the genome; they depend on the sequence of the genome and the frequency with which the restriction enzyme recognition site is found in the genome.
t
You have an oligonucleotide probe that hybridizes to part of gene A from a eucaryotic cell. Indicate whether a cDNA library (a) or a genomic DNA library (b) will be more appropriate for use in the following applications. You discover that gene A is alternatively spliced and you want to see which predicted alternative splice products the cell actually produces.
cDNA
Which of the following limits the use of PCR to detect and isolate genes?
The sequence at the beginning and end of the DNA to be amplified must be known.
The technique of 56 hybridization can be used to detect a specific RNA expression in a particular region of the brain.
in situ
True or false: During Southern blotting, double-stranded DNA is loaded onto the agarose gel. The DNA becomes denatured (and thus single stranded) as it gets transferred by the alkali solution from the gel to the nitrocellulose or nylon sheet.
t
True or false: A labeled DNA probe binds to the DNA by hybridization.
t
A piece of DNA used to detect a specific sequence in a nucleic acid by hybridization is known as a(n) __.
probe
In situ hybridization can be used to determine the _________________.
distribution of a given type of mRNA in different tissues
Millions of copies of a DNA sequence can be made entirely in vitro by the 26 technique.
Gel electrophoresis
Northern blotting detects a specific sequence in 57.
RNA
True or false: Some restriction nucleases cut in a staggered fashion, leaving short single-stranded regions of DNA at the ends of the cut molecule.
t
True or false: A reproducible set of DNA fragments will be produced every time a restriction nuclease digests a known piece of DNA.
t
You have an oligonucleotide probe that hybridizes to part of gene A from a eucaryotic cell.Indicate whether a cDNA library (a) or a genomic DNA library (b) will be more appropriate for use in the following applications. Gene A encodes a tRNA and you wish to isolate a piece of DNA containing the full-length sequence of the tRNA
Genomic DNA
true or false: PCR is particularly powerful because after each cycle of replication, there is a linear increase in the amount of DNA available.
f
During gel electrophoresis, DNA fragments _______________________.
travel through a matrix containing a microscopic network of pores
A DNA library has been constructed by purifying chromosomal DNA from mice, cutting the DNA with the restriction enzyme NotI, and inserting the fragments into the NotI site of a plasmid vector. What information cannot be retrieved from this library?
sequences of the telomeres
You have an oligonucleotide probe that hybridizes to part of gene A from a eucaryotic cell.Indicate whether a cDNA library (a) or a genomic DNA library (b) will be more appropriate for use in the following applications. You want to study the promoter of a gene A.
Genomic DNA
true or false You want to design a DNA probe used for hybridization to isolate a clone from a cDNA library.: The shorter the DNA probe used to probe the library, the greater the number of colonies to which the probe will hybridize.
t
True or false: A RE that has a 4-base-pair recognition sequence cuts on average once every 44 or 256 base pairs; one that has a 6-base-pair recognition sequence cuts once every 46 or 4096 base pairs; one that has an 8-base-pair recognition sequence cuts once every 48 or 65,536 base pairs; one that has a 12- base-pair recognition sequence cuts once every 412 or 16 million base pairs. To obtain fragments of about 70 kb in size, you would cut with a nuclease that recognizes an 8-base-pair site.
false
Southern blotting detects a specific sequence in 58.
DNA