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A double stranded DNA was denatured in a mixture that included mRNA from a gene in the segment. The mixture was then cooled to promote RNA and DNA hybridization. The following figure the results.

enter image description here

Which strand is DNA/RNA? What is source of the genetic material (Prokaryotic/Eukaryotic)? Which segment is exon/intron?

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Give us at least a try of your thoughts. The answer is not very complicated. – Chris May 27 '14 at 10:28
I thought P is exon and Q is intron. I is RNA and II is DNA from bacterial cell – Rudstar May 27 '14 at 10:31

You are almost right. I modified you picture a little bit to answer it:

enter image description here

Structure I is indeed DNA, structure II is processed RNA. This is because in I you see loop structures which have no complementary part in the RNA anymore, these are introns (structure Q and the flanking loop regions to P). P is an exon flanked by two introns. The end of the RNA is not complementary to the DNA because the poly-A tail has been added here.

The DNA is eukaryotic since you have introns and exons (which are not present in bacteria) and since the processed RNA contains a poly-A tail (which is also not present in bacteria).

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Everything is fine except that from this figure you cannot conclusively say that RNA is poly-A tailed. – WYSIWYG May 27 '14 at 12:32
This is the 3' region in which DNA and RNA can not hybridize. Additionally you could also think about a 3' untranslated region there. – Chris May 27 '14 at 13:50

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