Which of the following is true of the sequences found in DNA libraries from human tissues?
A) Those in a muscle cDNA library should all be present in a brain genomic library.
B) Those in a brain cDNA library should not be found within a muscle genomic library.
C) Those in a brain cDNA library should all be present a muscle cDNA library.
D) Those in a muscle genomic library should not be found within a brain genomic library.
E) Those in a muscle cDNA library should all be present in a brain cDNA library.

Question

Quizplus · Accepted Answer

cDNA libraries are made from mRNA and represent the genes that are being expressed in the tissue from which the mRNA was isolated. Since a genomic library contains all the sequences present in the genome, including those not being expressed in a particular tissue, sequences in a tissue-specific cDNA library (like muscle) should also be present in any tissue's genomic library (like brain), because the genomic library represents the entire set of genetic information in an organism, regardless of tissue-specific expression.

Which of the Following Is True of the Sequences Found