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?
(a) gene regulatory sequences
(b) intron sequences
(c) sequences of the telomeres (the ends of the chromosomes)
(d) amino acid sequences of proteins
(c) The very ends of all of the chromosomes are unlikely to be NotI sites, meaning that the fragments containing the ends of the chromosomes will not be able to insert into the bacterial vector (because they have not been cut by NotI at both ends) and will be lost from the library. All sequences present in genomic DNA (which includes regulatory sequences and introns) should be present in a genomic library. The coding sequence of the gene (and hence the amino acid sequence of the encoded protein) is also present in a genomic clone, although it is interrupted by intron sequences and is therefore somewhat difficult (but not impossible) to determine.
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A. epithelial. B. connective. C. nervous. D. muscle. E. All of the answer choices are correct.
Are humans responsible for neurotoxic shellfish poisoning? What will be an ideal response?
The nucleotide sequences on DNA that actually have information encoding a sequence of amino acids are
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