Problem:
Question 1: Three different alcohols are used in the experiment "isolation of the genomic DNA", namely ethanol, isopropanol, and phenol? The first two are freely soluble in water, but phenol is not and forms a non-miscible layer beneath aqueous solutions. Yet phenol has a much more acidic hydroxyl group than ethanol and isopropanol. Explain the solubility difference.
Question 2: Nucleic acids are precipitated from aqueous solutions by the addition of salt and an alcohol such as ethanol or isopropanol. Why is isopropanol more effective than ethanol in precipitating DNA?
Question 3: Why does the chromosomal DNA appear striated or streaky in the gel photo?
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