if the isolated DNA is not treated RNase, then RNA are present, but how come RNA molecules don’t get separated like the digested DNA fragments? aren’t they also in different sizes?
They get separated like DNA, but remember how many different RNA molecules are in a cell,its not like chromosomes or fragments of restriction digests having a discrete size. Apart from this if you do not carefully prepare your samples RNAse contamination can occur quite often…
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